TSQLStructure.cxx

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// @(#)root/sql:$Id$
// Author: Sergey Linev  20/11/2005

/*************************************************************************
 * Copyright (C) 1995-2005, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/

/**
\class TSQLStructure
\ingroup IO
This is hierarchical structure, which is created when data is written
by TBufferSQL2. It contains data all structural information such:
version of written class, data member types of that class, value for
each data member and so on.
Such structure in some sense similar to XML node and subnodes structure
Once it created, it converted to SQL statements, which are submitted
to database server.
*/

#include "TSQLStructure.h"

#include "Riostream.h"
#include "TMap.h"
#include "TClass.h"
#include "TStreamerInfo.h"
#include "TStreamerElement.h"
#include "TObjString.h"
#include "TClonesArray.h"

#include "TSQLFile.h"
#include "TSQLClassInfo.h"
#include "TSQLObjectData.h"
#include "TBufferSQL2.h"

#include "TSQLStatement.h"
#include "TSQLServer.h"
#include "TDataType.h"

namespace sqlio {
const Int_t Ids_NullPtr = 0;       // used to identify NULL pointer in tables
const Int_t Ids_RootDir = 0;       // dir:id, used for keys stored in root directory.
const Int_t Ids_TSQLFile = 0;      // keyid for TSQLFile entry in keys list
const Int_t Ids_StreamerInfos = 1; // keyid used to store StreamerInfos in ROOT directory
const Int_t Ids_FirstKey = 10;     // first key id, which is used in KeysTable (beside streamer info or something else)
const Int_t Ids_FirstObject = 1;   // first object id, allowed in object tables

const char *ObjectRef = "ObjectRef";
const char *ObjectRef_Arr = "ObjectRefArr";
const char *ObjectPtr = "ObjectPtr";
const char *ObjectInst = "ObjectInst";
const char *Version = "Version";
const char *TObjectUniqueId = "UniqueId";
const char *TObjectBits = "Bits";
const char *TObjectProcessId = "ProcessId";
const char *TStringValue = "StringValue";
const char *IndexSepar = "..";
const char *RawSuffix = ":rawdata";
const char *ParentSuffix = ":parent";
const char *ObjectSuffix = ":object";
const char *PointerSuffix = ":pointer";
const char *StrSuffix = ":str";
const char *LongStrPrefix = "#~#";

const char *Array = "Array";
const char *Bool = "Bool_t";
const char *Char = "Char_t";
const char *Short = "Short_t";
const char *Int = "Int_t";
const char *Long = "Long_t";
const char *Long64 = "Long64_t";
const char *Float = "Float_t";
const char *Double = "Double_t";
const char *UChar = "UChar_t";
const char *UShort = "UShort_t";
const char *UInt = "UInt_t";
const char *ULong = "ULong_t";
const char *ULong64 = "ULong64_t";
const char *CharStar = "CharStar";
const char *True = "1";
const char *False = "0";

// standard tables names
const char *KeysTable = "KeysTable";
const char *KeysTableIndex = "KeysTableIndex";
const char *ObjectsTable = "ObjectsTable";
const char *ObjectsTableIndex = "ObjectsTableIndex";
const char *IdsTable = "IdsTable";
const char *IdsTableIndex = "IdsTableIndex";
const char *StringsTable = "StringsTable";
const char *ConfigTable = "Configurations";

// columns in Keys table
const char *KT_Name = "Name";
const char *KT_Title = "Title";
const char *KT_Datetime = "Datime";
const char *KT_Cycle = "Cycle";
const char *KT_Class = "Class";

const char *DT_Create = "CreateDatime";
const char *DT_Modified = "ModifiedDatime";
const char *DT_UUID = "UUID";

// columns in Objects table
const char *OT_Class = "Class";
const char *OT_Version = "Version";

// columns in Identifiers Table
const char *IT_TableID = "TableId";
const char *IT_SubID = "SubId";
const char *IT_Type = "Type";
const char *IT_FullName = "FullName";
const char *IT_SQLName = "SQLName";
const char *IT_Info = "Info";

// colummns in _streamer_ tables
const char *BT_Field = "Field";
const char *BT_Value = "Value";

// colummns in string table
const char *ST_Value = "LongStringValue";

// columns in config table
const char *CT_Field = "Field";
const char *CT_Value = "Value";

// values in config table
const char *cfg_Version = "SQL_IO_version";
const char *cfg_UseSufixes = "UseNameSuffix";
const char *cfg_ArrayLimit = "ArraySizeLimit";
const char *cfg_TablesType = "TablesType";
const char *cfg_UseTransactions = "UseTransactions";
const char *cfg_UseIndexes = "UseIndexes";
const char *cfg_LockingMode = "LockingMode";
const char *cfg_ModifyCounter = "ModifyCounter";
};

//________________________________________________________________________

#ifdef R__VISUAL_CPLUSPLUS
#define FLong64 "%I64d"
#define FULong64 "%I64u"
#else
#define FLong64 "%lld"
#define FULong64 "%llu"
#endif

Long64_t sqlio::atol64(const char *value)
{
   if ((value == 0) || (*value == 0))
      return 0;
   Long64_t res = 0;
   sscanf(value, FLong64, &res);
   return res;
}

/**
\class TSQLColumnData
\ingroup IO
*/

ClassImp(TSQLColumnData);

////////////////////////////////////////////////////////////////////////////////
/// default constructor

TSQLColumnData::TSQLColumnData() : TObject(), fName(), fType(), fValue(), fNumeric(kFALSE)
{
}

////////////////////////////////////////////////////////////////////////////////
/// normal constructor of TSQLColumnData class
/// specifies name, type and value for one column

TSQLColumnData::TSQLColumnData(const char *name, const char *sqltype, const char *value, Bool_t numeric)
   : TObject(), fName(name), fType(sqltype), fValue(value), fNumeric(numeric)
{
}

////////////////////////////////////////////////////////////////////////////////
/// constructs TSQLColumnData object for integer column

TSQLColumnData::TSQLColumnData(const char *name, Long64_t value)
   : TObject(), fName(name), fType("INT"), fValue(), fNumeric(kTRUE)
{
   fValue.Form("%lld", value);
}

////////////////////////////////////////////////////////////////////////////////
/// TSQLColumnData destructor

TSQLColumnData::~TSQLColumnData()
{
}

ClassImp(TSQLTableData);

////////////////////////////////////////////////////////////////////////////////
/// normal constructor

TSQLTableData::TSQLTableData(TSQLFile *f, TSQLClassInfo *info)
   : TObject(), fFile(f), fInfo(info), fColumns(), fColInfos(0)
{
   if (info && !info->IsClassTableExist())
      fColInfos = new TObjArray;
}

////////////////////////////////////////////////////////////////////////////////
/// destructor

TSQLTableData::~TSQLTableData()
{
   fColumns.Delete();
   if (fColInfos != 0) {
      fColInfos->Delete();
      delete fColInfos;
   }
}

////////////////////////////////////////////////////////////////////////////////
/// Add INT column to list of columns

void TSQLTableData::AddColumn(const char *name, Long64_t value)
{
   TObjString *v = new TObjString(Form("%lld", value));
   v->SetBit(BIT(20), kTRUE);
   fColumns.Add(v);

   //   TSQLColumnData* col = new TSQLColumnData(name, value);
   //   fColumns.Add(col);

   if (fColInfos != 0)
      fColInfos->Add(new TSQLClassColumnInfo(name, DefineSQLName(name), "INT"));
}

////////////////////////////////////////////////////////////////////////////////
/// Add normal column to list of columns

void TSQLTableData::AddColumn(const char *name, const char *sqltype, const char *value, Bool_t numeric)
{
   TObjString *v = new TObjString(value);
   v->SetBit(BIT(20), numeric);
   fColumns.Add(v);

   //   TSQLColumnData* col = new TSQLColumnData(name, sqltype, value, numeric);
   //   fColumns.Add(col);

   if (fColInfos != 0)
      fColInfos->Add(new TSQLClassColumnInfo(name, DefineSQLName(name), sqltype));
}

////////////////////////////////////////////////////////////////////////////////
/// produce suitable name for column, taking into account length limitation

TString TSQLTableData::DefineSQLName(const char *fullname)
{
   Int_t maxlen = fFile->SQLMaxIdentifierLength();

   Int_t len = strlen(fullname);

   if ((len <= maxlen) && !HasSQLName(fullname))
      return TString(fullname);

   Int_t cnt = -1;
   TString res, scnt;

   do {

      scnt.Form("%d", cnt);
      Int_t numlen = cnt < 0 ? 0 : scnt.Length();

      res = fullname;

      if (len + numlen > maxlen)
         res.Resize(maxlen - numlen);

      if (cnt >= 0)
         res += scnt;

      if (!HasSQLName(res.Data()))
         return res;

      cnt++;

   } while (cnt < 10000);

   Error("DefineSQLName", "Cannot find reasonable column name for field %s", fullname);

   return TString(fullname);
}

////////////////////////////////////////////////////////////////////////////////
/// checks if columns list already has that sql name

Bool_t TSQLTableData::HasSQLName(const char *sqlname)
{
   TIter next(fColInfos);

   TSQLClassColumnInfo *col = 0;

   while ((col = (TSQLClassColumnInfo *)next()) != 0) {
      const char *colname = col->GetSQLName();
      if (strcmp(colname, sqlname) == 0)
         return kTRUE;
   }

   return kFALSE;
}

////////////////////////////////////////////////////////////////////////////////
/// returns number of columns in provided set

Int_t TSQLTableData::GetNumColumns()
{
   return fColumns.GetLast() + 1;
}

////////////////////////////////////////////////////////////////////////////////
/// return column value

const char *TSQLTableData::GetColumn(Int_t n)
{
   return fColumns[n]->GetName();
}

////////////////////////////////////////////////////////////////////////////////
/// identifies if column has numeric value

Bool_t TSQLTableData::IsNumeric(Int_t n)
{
   return fColumns[n]->TestBit(BIT(20));
}

////////////////////////////////////////////////////////////////////////////////
/// take ownership over colinfos

TObjArray *TSQLTableData::TakeColInfos()
{
   TObjArray *res = fColInfos;
   fColInfos = 0;
   return res;
}

//________________________________________________________________________

ClassImp(TSQLStructure);

TSQLStructure::TSQLStructure()
   : TObject(), fParent(0), fType(0), fPointer(0), fValue(), fArrayIndex(-1), fRepeatCnt(0), fChilds()
{
   // default constructor
}

////////////////////////////////////////////////////////////////////////////////
/// destructor

TSQLStructure::~TSQLStructure()
{
   fChilds.Delete();
   if (GetType() == kSqlObjectData) {
      TSQLObjectData *objdata = (TSQLObjectData *)fPointer;
      delete objdata;
   } else if (GetType() == kSqlCustomElement) {
      TStreamerElement *elem = (TStreamerElement *)fPointer;
      delete elem;
   }
}

////////////////////////////////////////////////////////////////////////////////
/// number of child structures

Int_t TSQLStructure::NumChilds() const
{
   return fChilds.GetLast() + 1;
}

////////////////////////////////////////////////////////////////////////////////
/// return child structure of index n

TSQLStructure *TSQLStructure::GetChild(Int_t n) const
{
   return (n < 0) || (n > fChilds.GetLast()) ? 0 : (TSQLStructure *)fChilds[n];
}

////////////////////////////////////////////////////////////////////////////////
/// set structure type as kSqlObject

void TSQLStructure::SetObjectRef(Long64_t refid, const TClass *cl)
{
   fType = kSqlObject;
   fValue.Form("%lld", refid);
   fPointer = cl;
}

////////////////////////////////////////////////////////////////////////////////
/// set structure type as kSqlPointer

void TSQLStructure::SetObjectPointer(Long64_t ptrid)
{
   fType = kSqlPointer;
   fValue.Form("%lld", ptrid);
}

////////////////////////////////////////////////////////////////////////////////
/// set structure type as kSqlVersion

void TSQLStructure::SetVersion(const TClass *cl, Int_t version)
{
   fType = kSqlVersion;
   fPointer = cl;
   if (version < 0)
      version = cl->GetClassVersion();
   fValue.Form("%d", version);
}

////////////////////////////////////////////////////////////////////////////////
/// set structure type as kSqlClassStreamer

void TSQLStructure::SetClassStreamer(const TClass *cl)
{
   fType = kSqlClassStreamer;
   fPointer = cl;
}

////////////////////////////////////////////////////////////////////////////////
/// set structure type as kSqlStreamerInfo

void TSQLStructure::SetStreamerInfo(const TStreamerInfo *info)
{
   fType = kSqlStreamerInfo;
   fPointer = info;
}

////////////////////////////////////////////////////////////////////////////////
/// set structure type as kSqlElement

void TSQLStructure::SetStreamerElement(const TStreamerElement *elem, Int_t number)
{
   fType = kSqlElement;
   fPointer = elem;
   fArrayIndex = number;
}

////////////////////////////////////////////////////////////////////////////////
/// set structure type as kSqlCustomClass

void TSQLStructure::SetCustomClass(const TClass *cl, Version_t version)
{
   fType = kSqlCustomClass;
   fPointer = (void *)cl;
   fArrayIndex = version;
}

////////////////////////////////////////////////////////////////////////////////
/// set structure type as kSqlCustomElement

void TSQLStructure::SetCustomElement(TStreamerElement *elem)
{
   fType = kSqlCustomElement;
   fPointer = elem;
}

////////////////////////////////////////////////////////////////////////////////
/// set structure type as kSqlValue

void TSQLStructure::SetValue(const char *value, const char *tname)
{
   fType = kSqlValue;
   fValue = value;
   fPointer = tname;
}

////////////////////////////////////////////////////////////////////////////////
/// change value of this structure
/// used as "workaround" to keep object id in kSqlElement node

void TSQLStructure::ChangeValueOnly(const char *value)
{
   fValue = value;
}

////////////////////////////////////////////////////////////////////////////////
/// set array index for this structure

void TSQLStructure::SetArrayIndex(Int_t indx, Int_t cnt)
{
   fArrayIndex = indx;
   fRepeatCnt = cnt;
}

////////////////////////////////////////////////////////////////////////////////
/// set array index for last child element
///   if (cnt<=1) return;

void TSQLStructure::ChildArrayIndex(Int_t index, Int_t cnt)
{
   TSQLStructure *last = (TSQLStructure *)fChilds.Last();
   if ((last != 0) && (last->GetType() == kSqlValue))
      last->SetArrayIndex(index, cnt);
}

////////////////////////////////////////////////////////////////////////////////
/// Set structure as array element

void TSQLStructure::SetArray(Int_t sz)
{
   fType = kSqlArray;
   if (sz >= 0)
      fValue.Form("%d", sz);
}

////////////////////////////////////////////////////////////////////////////////
/// return object class if type kSqlObject

TClass *TSQLStructure::GetObjectClass() const
{
   return (fType == kSqlObject) ? (TClass *)fPointer : 0;
}

////////////////////////////////////////////////////////////////////////////////
/// return class for version tag if type is kSqlVersion

TClass *TSQLStructure::GetVersionClass() const
{
   return (fType == kSqlVersion) ? (TClass *)fPointer : 0;
}

////////////////////////////////////////////////////////////////////////////////
/// return TStreamerInfo* if type is kSqlStreamerInfo

TStreamerInfo *TSQLStructure::GetStreamerInfo() const
{
   return (fType == kSqlStreamerInfo) ? (TStreamerInfo *)fPointer : 0;
}

////////////////////////////////////////////////////////////////////////////////
/// return TStremerElement* if type is kSqlElement

TStreamerElement *TSQLStructure::GetElement() const
{
   return (fType == kSqlElement) || (fType == kSqlCustomElement) ? (TStreamerElement *)fPointer : 0;
}

////////////////////////////////////////////////////////////////////////////////
/// returns number of TStremerElement in TStreamerInfo

Int_t TSQLStructure::GetElementNumber() const
{
   return (fType == kSqlElement) ? fArrayIndex : 0;
}

////////////////////////////////////////////////////////////////////////////////
/// return value type if structure is kSqlValue

const char *TSQLStructure::GetValueType() const
{
   return (fType == kSqlValue) ? (const char *)fPointer : 0;
}

////////////////////////////////////////////////////////////////////////////////
/// return element custom class if strutures is kSqlCustomClass

TClass *TSQLStructure::GetCustomClass() const
{
   return (fType == kSqlCustomClass) ? (TClass *)fPointer : 0;
}

////////////////////////////////////////////////////////////////////////////////
/// return custom class version if strutures is kSqlCustomClass

Version_t TSQLStructure::GetCustomClassVersion() const
{
   return (fType == kSqlCustomClass) ? fArrayIndex : 0;
}

////////////////////////////////////////////////////////////////////////////////
/// provides class info if structure kSqlStreamerInfo or kSqlCustomClass

Bool_t TSQLStructure::GetClassInfo(TClass *&cl, Version_t &version)
{
   if (GetType() == kSqlStreamerInfo) {
      TStreamerInfo *info = GetStreamerInfo();
      if (info == 0)
         return kFALSE;
      cl = info->GetClass();
      version = info->GetClassVersion();
   } else if (GetType() == kSqlCustomClass) {
      cl = GetCustomClass();
      version = GetCustomClassVersion();
   } else
      return kFALSE;
   return kTRUE;
}

////////////////////////////////////////////////////////////////////////////////
/// returns value
/// for different structure kinds has different sense
/// For kSqlVersion it version, for kSqlReference it is object id and so on

const char *TSQLStructure::GetValue() const
{
   return fValue.Data();
}

////////////////////////////////////////////////////////////////////////////////
/// Add child structure

void TSQLStructure::Add(TSQLStructure *child)
{
   if (child != 0) {
      child->SetParent(this);
      fChilds.Add(child);
   }
}

////////////////////////////////////////////////////////////////////////////////
/// add child as version

void TSQLStructure::AddVersion(const TClass *cl, Int_t version)
{
   TSQLStructure *ver = new TSQLStructure;
   ver->SetVersion(cl, version);
   Add(ver);
}

////////////////////////////////////////////////////////////////////////////////
/// Add child structure as value

void TSQLStructure::AddValue(const char *value, const char *tname)
{
   TSQLStructure *child = new TSQLStructure;
   child->SetValue(value, tname);
   Add(child);
}

////////////////////////////////////////////////////////////////////////////////
/// defines current object id, to which this structure belong
/// make life complicated, because some objects do not get id
/// automatically in TBufferSQL, but afterwards

Long64_t TSQLStructure::DefineObjectId(Bool_t recursive)
{
   TSQLStructure *curr = this;
   while (curr != 0) {
      if ((curr->GetType() == kSqlObject) || (curr->GetType() == kSqlPointer) ||
          // workaround to store object id in element structure
          (curr->GetType() == kSqlElement) || (curr->GetType() == kSqlCustomElement) ||
          (curr->GetType() == kSqlCustomClass) || (curr->GetType() == kSqlStreamerInfo)) {
         const char *value = curr->GetValue();
         if ((value != 0) && (strlen(value) > 0))
            return sqlio::atol64(value);
      }

      curr = recursive ? curr->GetParent() : 0;
   }
   return -1;
}

////////////////////////////////////////////////////////////////////////////////
/// set element to be used for object data

void TSQLStructure::SetObjectData(TSQLObjectData *objdata)
{
   fType = kSqlObjectData;
   fPointer = objdata;
}

////////////////////////////////////////////////////////////////////////////////
/// add element with pointer to object data

void TSQLStructure::AddObjectData(TSQLObjectData *objdata)
{
   TSQLStructure *child = new TSQLStructure;
   child->SetObjectData(objdata);
   Add(child);
}

////////////////////////////////////////////////////////////////////////////////
/// searches for objects data

TSQLObjectData *TSQLStructure::GetObjectData(Bool_t search)
{
   TSQLStructure *child = GetChild(0);
   if ((child != 0) && (child->GetType() == kSqlObjectData))
      return (TSQLObjectData *)child->fPointer;
   if (search && (GetParent() != 0))
      return GetParent()->GetObjectData(search);
   return 0;
}

////////////////////////////////////////////////////////////////////////////////
/// print content of complete structure

void TSQLStructure::Print(Option_t *) const
{
   PrintLevel(0);
}

////////////////////////////////////////////////////////////////////////////////
/// print content of current structure

void TSQLStructure::PrintLevel(Int_t level) const
{
   for (Int_t n = 0; n < level; n++)
      std::cout << " ";
   switch (fType) {
   case 0: std::cout << "Undefined type"; break;
   case kSqlObject: std::cout << "Object ref = " << fValue; break;
   case kSqlPointer: std::cout << "Pointer ptr = " << fValue; break;
   case kSqlVersion: {
      const TClass *cl = (const TClass *)fPointer;
      std::cout << "Version cl = " << cl->GetName() << " ver = " << cl->GetClassVersion();
      break;
   }
   case kSqlStreamerInfo: {
      const TStreamerInfo *info = (const TStreamerInfo *)fPointer;
      std::cout << "Class: " << info->GetName();
      break;
   }
   case kSqlCustomElement:
   case kSqlElement: {
      const TStreamerElement *elem = (const TStreamerElement *)fPointer;
      std::cout << "Member: " << elem->GetName();
      break;
   }
   case kSqlValue: {
      std::cout << "Value: " << fValue;
      if (fRepeatCnt > 1)
         std::cout << "  cnt:" << fRepeatCnt;
      if (fPointer != 0)
         std::cout << "  type = " << (const char *)fPointer;
      break;
   }
   case kSqlArray: {
      std::cout << "Array ";
      if (fValue.Length() > 0)
         std::cout << "  sz = " << fValue;
      break;
   }
   case kSqlCustomClass: {
      TClass *cl = (TClass *)fPointer;
      std::cout << "CustomClass: " << cl->GetName() << "  ver = " << fValue;
      break;
   }
   default: std::cout << "Unknown type";
   }
   std::cout << std::endl;

   for (Int_t n = 0; n < NumChilds(); n++)
      GetChild(n)->PrintLevel(level + 2);
}

////////////////////////////////////////////////////////////////////////////////
/// defines if value is numeric and not requires quotes when writing

Bool_t TSQLStructure::IsNumericType(Int_t typ)
{
   switch (typ) {
   case TStreamerInfo::kShort: return kTRUE;
   case TStreamerInfo::kInt: return kTRUE;
   case TStreamerInfo::kLong: return kTRUE;
   case TStreamerInfo::kFloat: return kTRUE;
   case TStreamerInfo::kFloat16: return kTRUE;
   case TStreamerInfo::kCounter: return kTRUE;
   case TStreamerInfo::kDouble: return kTRUE;
   case TStreamerInfo::kDouble32: return kTRUE;
   case TStreamerInfo::kUChar: return kTRUE;
   case TStreamerInfo::kUShort: return kTRUE;
   case TStreamerInfo::kUInt: return kTRUE;
   case TStreamerInfo::kULong: return kTRUE;
   case TStreamerInfo::kBits: return kTRUE;
   case TStreamerInfo::kLong64: return kTRUE;
   case TStreamerInfo::kULong64: return kTRUE;
   case TStreamerInfo::kBool: return kTRUE;
   }
   return kFALSE;
}

////////////////////////////////////////////////////////////////////////////////
/// provides name for basic types
/// used as suffix for column name or field suffix in raw table

const char *TSQLStructure::GetSimpleTypeName(Int_t typ)
{
   switch (typ) {
   case TStreamerInfo::kChar: return sqlio::Char;
   case TStreamerInfo::kShort: return sqlio::Short;
   case TStreamerInfo::kInt: return sqlio::Int;
   case TStreamerInfo::kLong: return sqlio::Long;
   case TStreamerInfo::kFloat: return sqlio::Float;
   case TStreamerInfo::kFloat16: return sqlio::Float;
   case TStreamerInfo::kCounter: return sqlio::Int;
   case TStreamerInfo::kDouble: return sqlio::Double;
   case TStreamerInfo::kDouble32: return sqlio::Double;
   case TStreamerInfo::kUChar: return sqlio::UChar;
   case TStreamerInfo::kUShort: return sqlio::UShort;
   case TStreamerInfo::kUInt: return sqlio::UInt;
   case TStreamerInfo::kULong: return sqlio::ULong;
   case TStreamerInfo::kBits: return sqlio::UInt;
   case TStreamerInfo::kLong64: return sqlio::Long64;
   case TStreamerInfo::kULong64: return sqlio::ULong64;
   case TStreamerInfo::kBool: return sqlio::Bool;
   }

   return 0;
}

//___________________________________________________________

// TSqlCmdsBuffer used as buffer for data, which are correspond to
// particular class, defined by TSQLClassInfo instance
// Support both TSQLStatement and Query modes

class TSqlCmdsBuffer : public TObject {

public:
   TSqlCmdsBuffer(TSQLFile *f, TSQLClassInfo *info) : TObject(), fFile(f), fInfo(info), fBlobStmt(0), fNormStmt(0) {}

   virtual ~TSqlCmdsBuffer()
   {
      fNormCmds.Delete();
      fBlobCmds.Delete();
      fFile->SQLDeleteStatement(fBlobStmt);
      fFile->SQLDeleteStatement(fNormStmt);
   }

   void AddValues(Bool_t isnorm, const char *values)
   {
      TObjString *str = new TObjString(values);
      if (isnorm)
         fNormCmds.Add(str);
      else
         fBlobCmds.Add(str);
   }

   TSQLFile *fFile;
   TSQLClassInfo *fInfo;
   TObjArray fNormCmds;
   TObjArray fBlobCmds;
   TSQLStatement *fBlobStmt;
   TSQLStatement *fNormStmt;
};

//________________________________________________________________________
// TSqlRegistry keeps data, used when object data transformed to sql query or
// statements

class TSqlRegistry : public TObject {

public:
   TSqlRegistry()
      : TObject(), fFile(0), fKeyId(0), fLastObjId(-1), fCmds(0), fFirstObjId(0), fCurrentObjId(0), fCurrentObjClass(0),
        fLastLongStrId(0), fPool(), fLongStrValues(), fRegValues(), fRegStmt(0)
   {
   }

   TSQLFile *fFile;
   Long64_t fKeyId;
   Long64_t fLastObjId;
   TObjArray *fCmds;
   Long64_t fFirstObjId;

   Long64_t fCurrentObjId;
   TClass *fCurrentObjClass;

   Int_t fLastLongStrId;

   TMap fPool;
   TObjArray fLongStrValues;
   TObjArray fRegValues;

   TSQLStatement *fRegStmt;

   virtual ~TSqlRegistry()
   {
      fPool.DeleteValues();
      fLongStrValues.Delete();
      fRegValues.Delete();
      fFile->SQLDeleteStatement(fRegStmt);
   }

   Long64_t GetNextObjId() { return ++fLastObjId; }

   void AddSqlCmd(const char *query)
   {
      // add SQL command to the list
      if (fCmds == 0)
         fCmds = new TObjArray;
      fCmds->Add(new TObjString(query));
   }

   TSqlCmdsBuffer *GetCmdsBuffer(TSQLClassInfo *sqlinfo)
   {
      if (sqlinfo == 0)
         return 0;
      TSqlCmdsBuffer *buf = (TSqlCmdsBuffer *)fPool.GetValue(sqlinfo);
      if (buf == 0) {
         buf = new TSqlCmdsBuffer(fFile, sqlinfo);
         fPool.Add(sqlinfo, buf);
      }
      return buf;
   }

   void ConvertSqlValues(TObjArray &values, const char *tablename)
   {
      // this function transforms array of values for one table
      // to SQL command. For MySQL one INSERT query can
      // contain data for more than one row

      if ((values.GetLast() < 0) || (tablename == 0))
         return;

      Bool_t canbelong = fFile->IsMySQL();

      Int_t maxsize = 50000;
      TString sqlcmd(maxsize), value, onecmd, cmdmask;

      const char *quote = fFile->SQLIdentifierQuote();

      TIter iter(&values);
      TObject *cmd = 0;
      while ((cmd = iter()) != 0) {

         if (sqlcmd.Length() == 0)
            sqlcmd.Form("INSERT INTO %s%s%s VALUES (%s)", quote, tablename, quote, cmd->GetName());
         else {
            sqlcmd += ", (";
            sqlcmd += cmd->GetName();
            sqlcmd += ")";
         }

         if (!canbelong || (sqlcmd.Length() > maxsize * 0.9)) {
            AddSqlCmd(sqlcmd.Data());
            sqlcmd = "";
         }
      }

      if (sqlcmd.Length() > 0)
         AddSqlCmd(sqlcmd.Data());
   }

   void ConvertPoolValues()
   {
      TSQLClassInfo *sqlinfo = 0;
      TIter iter(&fPool);
      while ((sqlinfo = (TSQLClassInfo *)iter()) != 0) {
         TSqlCmdsBuffer *buf = (TSqlCmdsBuffer *)fPool.GetValue(sqlinfo);
         if (buf == 0)
            continue;
         ConvertSqlValues(buf->fNormCmds, sqlinfo->GetClassTableName());
         // ensure that raw table will be created
         if (buf->fBlobCmds.GetLast() >= 0)
            fFile->CreateRawTable(sqlinfo);
         ConvertSqlValues(buf->fBlobCmds, sqlinfo->GetRawTableName());
         if (buf->fBlobStmt)
            buf->fBlobStmt->Process();
         if (buf->fNormStmt)
            buf->fNormStmt->Process();
      }

      ConvertSqlValues(fLongStrValues, sqlio::StringsTable);
      ConvertSqlValues(fRegValues, sqlio::ObjectsTable);
      if (fRegStmt)
         fRegStmt->Process();
   }

   void AddRegCmd(Long64_t objid, TClass *cl)
   {
      Long64_t indx = objid - fFirstObjId;
      if (indx < 0) {
         Error("AddRegCmd", "Something wrong with objid = %lld", objid);
         return;
      }

      if (fFile->IsOracle() || fFile->IsODBC()) {
         if ((fRegStmt == 0) && fFile->SQLCanStatement()) {
            const char *quote = fFile->SQLIdentifierQuote();

            TString sqlcmd;
            const char *pars = fFile->IsOracle() ? ":1, :2, :3, :4" : "?, ?, ?, ?";
            sqlcmd.Form("INSERT INTO %s%s%s VALUES (%s)", quote, sqlio::ObjectsTable, quote, pars);
            fRegStmt = fFile->SQLStatement(sqlcmd.Data(), 1000);
         }

         if (fRegStmt != 0) {
            fRegStmt->NextIteration();
            fRegStmt->SetLong64(0, fKeyId);
            fRegStmt->SetLong64(1, objid);
            fRegStmt->SetString(2, cl->GetName(), fFile->SQLSmallTextTypeLimit());
            fRegStmt->SetInt(3, cl->GetClassVersion());
            return;
         }
      }

      const char *valuequote = fFile->SQLValueQuote();
      TString cmd;
      cmd.Form("%lld, %lld, %s%s%s, %d", fKeyId, objid, valuequote, cl->GetName(), valuequote, cl->GetClassVersion());
      fRegValues.AddAtAndExpand(new TObjString(cmd), indx);
   }

   Int_t AddLongString(const char *strvalue)
   {
      // add value to special string table,
      // where large (more than 255 bytes) strings are stored

      if (fLastLongStrId == 0)
         fFile->VerifyLongStringTable();
      Int_t strid = ++fLastLongStrId;
      TString value = strvalue;
      const char *valuequote = fFile->SQLValueQuote();
      TSQLStructure::AddStrBrackets(value, valuequote);

      TString cmd;
      cmd.Form("%lld, %d, %s", fCurrentObjId, strid, value.Data());

      fLongStrValues.Add(new TObjString(cmd));

      return strid;
   }

   Bool_t InsertToNormalTableOracle(TSQLTableData *columns, TSQLClassInfo *sqlinfo)
   {
      TSqlCmdsBuffer *buf = GetCmdsBuffer(sqlinfo);
      if (buf == 0)
         return kFALSE;

      TSQLStatement *stmt = buf->fNormStmt;
      if (stmt == 0) {
         // if one cannot create statement, do it normal way
         if (!fFile->SQLCanStatement())
            return kFALSE;

         const char *quote = fFile->SQLIdentifierQuote();
         TString sqlcmd;
         sqlcmd.Form("INSERT INTO %s%s%s VALUES (", quote, sqlinfo->GetClassTableName(), quote);
         for (int n = 0; n < columns->GetNumColumns(); n++) {
            if (n > 0)
               sqlcmd += ", ";
            if (fFile->IsOracle()) {
               sqlcmd += ":";
               sqlcmd += (n + 1);
            } else
               sqlcmd += "?";
         }
         sqlcmd += ")";

         stmt = fFile->SQLStatement(sqlcmd.Data(), 1000);
         if (stmt == 0)
            return kFALSE;
         buf->fNormStmt = stmt;
      }

      stmt->NextIteration();

      Int_t sizelimit = fFile->SQLSmallTextTypeLimit();

      for (Int_t ncol = 0; ncol < columns->GetNumColumns(); ncol++) {
         const char *value = columns->GetColumn(ncol);
         if (value == 0)
            value = "";
         stmt->SetString(ncol, value, sizelimit);
      }

      return kTRUE;
   }

   void InsertToNormalTable(TSQLTableData *columns, TSQLClassInfo *sqlinfo)
   {
      // produce SQL query to insert object data into normal table

      if (fFile->IsOracle() || fFile->IsODBC())
         if (InsertToNormalTableOracle(columns, sqlinfo))
            return;

      const char *valuequote = fFile->SQLValueQuote();

      TString values;

      for (Int_t n = 0; n < columns->GetNumColumns(); n++) {
         if (n > 0)
            values += ", ";

         if (columns->IsNumeric(n))
            values += columns->GetColumn(n);
         else {
            TString value = columns->GetColumn(n);
            TSQLStructure::AddStrBrackets(value, valuequote);
            values += value;
         }
      }

      TSqlCmdsBuffer *buf = GetCmdsBuffer(sqlinfo);
      if (buf != 0)
         buf->AddValues(kTRUE, values.Data());
   }
};

//_____________________________________________________________________________

// TSqlRawBuffer is used to convert raw data, which corresponds to one
// object and belong to single SQL tables. Supports both statements
// and query mode

class TSqlRawBuffer : public TObject {

public:
   TSqlRawBuffer(TSqlRegistry *reg, TSQLClassInfo *sqlinfo)
      : TObject(), fFile(0), fInfo(0), fCmdBuf(0), fObjId(0), fRawId(0), fValueMask(), fValueQuote(0), fMaxStrSize(255)
   {
      fFile = reg->fFile;
      fInfo = sqlinfo;
      fCmdBuf = reg->GetCmdsBuffer(sqlinfo);
      fObjId = reg->fCurrentObjId;
      fValueQuote = fFile->SQLValueQuote();
      fValueMask.Form("%lld, %s, %s%s%s, %s", fObjId, "%d", fValueQuote, "%s", fValueQuote, "%s");
      fMaxStrSize = reg->fFile->SQLSmallTextTypeLimit();
   }

   virtual ~TSqlRawBuffer()
   {
      // close blob statement for Oracle
      TSQLStatement *stmt = fCmdBuf->fBlobStmt;
      if ((stmt != 0) && fFile->IsOracle()) {
         stmt->Process();
         delete stmt;
         fCmdBuf->fBlobStmt = 0;
      }
   }

   Bool_t IsAnyData() const { return fRawId > 0; }

   void AddLine(const char *name, const char *value, const char *topname = 0, const char *ns = 0)
   {
      if (fCmdBuf == 0)
         return;

      // when first line is created, check all problems
      if (fRawId == 0) {
         Bool_t maketmt = kFALSE;
         if (fFile->IsOracle() || fFile->IsODBC())
            maketmt = (fCmdBuf->fBlobStmt == 0) && fFile->SQLCanStatement();

         if (maketmt) {
            // ensure that raw table is exists
            fFile->CreateRawTable(fInfo);

            const char *quote = fFile->SQLIdentifierQuote();
            TString sqlcmd;
            const char *params = fFile->IsOracle() ? ":1, :2, :3, :4" : "?, ?, ?, ?";
            sqlcmd.Form("INSERT INTO %s%s%s VALUES (%s)", quote, fInfo->GetRawTableName(), quote, params);
            TSQLStatement *stmt = fFile->SQLStatement(sqlcmd.Data(), 2000);
            fCmdBuf->fBlobStmt = stmt;
         }
      }

      TString buf;
      const char *fullname = name;
      if ((topname != 0) && (ns != 0)) {
         buf += topname;
         buf += ns;
         buf += name;
         fullname = buf.Data();
      }

      TSQLStatement *stmt = fCmdBuf->fBlobStmt;

      if (stmt != 0) {
         stmt->NextIteration();
         stmt->SetLong64(0, fObjId);
         stmt->SetInt(1, fRawId++);
         stmt->SetString(2, fullname, fMaxStrSize);
         //         Info("AddLine","name = %s value = %s",fullname, value);
         stmt->SetString(3, value, fMaxStrSize);
      } else {
         TString valuebuf(value);
         TSQLStructure::AddStrBrackets(valuebuf, fValueQuote);
         TString cmd;
         cmd.Form(fValueMask.Data(), fRawId++, fullname, valuebuf.Data());
         fCmdBuf->AddValues(kFALSE, cmd.Data());
      }
   }

   TSQLFile *fFile;
   TSQLClassInfo *fInfo;
   TSqlCmdsBuffer *fCmdBuf;
   Long64_t fObjId;
   Int_t fRawId;
   TString fValueMask;
   const char *fValueQuote;
   Int_t fMaxStrSize;
};

////////////////////////////////////////////////////////////////////////////////
/// define maximum reference id, used for objects

Long64_t TSQLStructure::FindMaxObjectId()
{
   Long64_t max = DefineObjectId(kFALSE);

   for (Int_t n = 0; n < NumChilds(); n++) {
      Long64_t zn = GetChild(n)->FindMaxObjectId();
      if (zn > max)
         max = zn;
   }

   return max;
}

////////////////////////////////////////////////////////////////////////////////
/// Convert structure to sql statements
/// This function is called immidiately after TBufferSQL2 produces
/// this structure with object data
/// Should be only called for toplevel structure

Bool_t TSQLStructure::ConvertToTables(TSQLFile *file, Long64_t keyid, TObjArray *cmds)
{
   if ((file == 0) || (cmds == 0))
      return kFALSE;

   TSqlRegistry reg;

   reg.fCmds = cmds;
   reg.fFile = file;
   reg.fKeyId = keyid;
   // this is id of main object to be stored
   reg.fFirstObjId = DefineObjectId(kFALSE);
   // this is maximum objectid which is now in use
   reg.fLastObjId = FindMaxObjectId();

   Bool_t res = StoreObject(&reg, reg.fFirstObjId, GetObjectClass());

   // convert values from pool to SQL commands
   reg.ConvertPoolValues();

   return res;
}

////////////////////////////////////////////////////////////////////////////////
/// perform conversion of structure to sql statements
/// first tries convert it to normal form
/// if fails, produces data for raw table

void TSQLStructure::PerformConversion(TSqlRegistry *reg, TSqlRawBuffer *blobs, const char *topname, Bool_t useblob)
{
   TString sbuf;
   const char *ns = reg->fFile->SQLNameSeparator();

   switch (fType) {
   case kSqlObject: {

      if (!StoreObject(reg, DefineObjectId(kFALSE), GetObjectClass()))
         break;

      blobs->AddLine(sqlio::ObjectRef, GetValue(), topname, ns);

      break;
   }

   case kSqlPointer: {
      blobs->AddLine(sqlio::ObjectPtr, fValue.Data(), topname, ns);
      break;
   }

   case kSqlVersion: {
      if (fPointer != 0)
         topname = ((TClass *)fPointer)->GetName();
      else
         Error("PerformConversion", "version without class");
      blobs->AddLine(sqlio::Version, fValue.Data(), topname, ns);
      break;
   }

   case kSqlStreamerInfo: {

      TStreamerInfo *info = GetStreamerInfo();
      if (info == 0)
         return;

      if (useblob) {
         for (Int_t n = 0; n <= fChilds.GetLast(); n++) {
            TSQLStructure *child = (TSQLStructure *)fChilds.At(n);
            child->PerformConversion(reg, blobs, info->GetName(), useblob);
         }
      } else {
         Long64_t objid = reg->GetNextObjId();
         TString sobjid;
         sobjid.Form("%lld", objid);
         if (!StoreObject(reg, objid, info->GetClass(), kTRUE))
            return;
         blobs->AddLine(sqlio::ObjectInst, sobjid.Data(), topname, ns);
      }
      break;
   }

   case kSqlCustomElement:
   case kSqlElement: {
      const TStreamerElement *elem = (const TStreamerElement *)fPointer;

      Int_t indx = 0;
      while (indx < NumChilds()) {
         TSQLStructure *child = GetChild(indx++);
         child->PerformConversion(reg, blobs, elem->GetName(), useblob);
      }
      break;
   }

   case kSqlValue: {
      const char *tname = (const char *)fPointer;
      if (fArrayIndex >= 0) {
         if (fRepeatCnt > 1)
            sbuf.Form("%s%d%s%d%s%s%s", "[", fArrayIndex, sqlio::IndexSepar, fArrayIndex + fRepeatCnt - 1, "]", ns,
                      tname);
         else
            sbuf.Form("%s%d%s%s%s", "[", fArrayIndex, "]", ns, tname);
      } else {
         if (tname != 0)
            sbuf = tname;
         else
            sbuf = "Value";
      }

      TString buf;
      const char *value = fValue.Data();

      if ((tname == sqlio::CharStar) && (value != 0)) {
         Int_t size = strlen(value);
         if (size > reg->fFile->SQLSmallTextTypeLimit()) {
            Int_t strid = reg->AddLongString(value);
            buf = reg->fFile->CodeLongString(reg->fCurrentObjId, strid);
            value = buf.Data();
         }
      }

      blobs->AddLine(sbuf.Data(), value, (fArrayIndex >= 0) ? 0 : topname, ns);

      break;
   }

   case kSqlArray: {
      if (fValue.Length() > 0)
         blobs->AddLine(sqlio::Array, fValue.Data(), topname, ns);
      for (Int_t n = 0; n <= fChilds.GetLast(); n++) {
         TSQLStructure *child = (TSQLStructure *)fChilds.At(n);
         child->PerformConversion(reg, blobs, topname, useblob);
      }
      break;
   }
   }
}

////////////////////////////////////////////////////////////////////////////////
/// convert object data to sql statements
/// if normal (column-wise) representation is not possible,
/// complete object will be converted to raw format

Bool_t TSQLStructure::StoreObject(TSqlRegistry *reg, Long64_t objid, TClass *cl, Bool_t registerobj)
{
   if ((cl == 0) || (objid < 0))
      return kFALSE;

   if (gDebug > 1) {
      std::cout << "Store object " << objid << " cl = " << cl->GetName() << std::endl;
      if (GetStreamerInfo())
         std::cout << "Info = " << GetStreamerInfo()->GetName() << std::endl;
      else if (GetElement())
         std::cout << "Element = " << GetElement()->GetName() << std::endl;
   }

   Long64_t oldid = reg->fCurrentObjId;
   TClass *oldcl = reg->fCurrentObjClass;

   reg->fCurrentObjId = objid;
   reg->fCurrentObjClass = cl;

   Bool_t normstore = kFALSE;

   Bool_t res = kTRUE;

   if (cl == TObject::Class())
      normstore = StoreTObject(reg);
   else if (cl == TString::Class())
      normstore = StoreTString(reg);
   else if (GetType() == kSqlStreamerInfo)
      // this is a case when array of objects are stored in blob and each object
      // has normal streamer. Then it will be stored in normal form and only one tag
      // will be kept to remind about
      normstore = StoreClassInNormalForm(reg);
   else
      normstore = StoreObjectInNormalForm(reg);

   if (gDebug > 2)
      std::cout << "Store object " << objid << " of class " << cl->GetName() << "  normal = " << normstore
                << " sqltype = " << GetType() << std::endl;

   if (!normstore) {

      // This is a case, when only raw table is exists

      TSQLClassInfo *sqlinfo = reg->fFile->RequestSQLClassInfo(cl);
      TSqlRawBuffer rawdata(reg, sqlinfo);

      for (Int_t n = 0; n < NumChilds(); n++) {
         TSQLStructure *child = GetChild(n);
         child->PerformConversion(reg, &rawdata, 0 /*cl->GetName()*/);
      }

      res = rawdata.IsAnyData();
   }

   if (registerobj)
      reg->AddRegCmd(objid, cl);

   reg->fCurrentObjId = oldid;
   reg->fCurrentObjClass = oldcl;

   return res;
}

////////////////////////////////////////////////////////////////////////////////
/// this function verify object child elements and
/// calls transformation to class table

Bool_t TSQLStructure::StoreObjectInNormalForm(TSqlRegistry *reg)
{
   if (fChilds.GetLast() != 1)
      return kFALSE;

   TSQLStructure *s_ver = GetChild(0);

   TSQLStructure *s_info = GetChild(1);

   if (!CheckNormalClassPair(s_ver, s_info))
      return kFALSE;

   return s_info->StoreClassInNormalForm(reg);
}

////////////////////////////////////////////////////////////////////////////////
/// produces data for complete class table
/// where not possible, raw data for some elements are created

Bool_t TSQLStructure::StoreClassInNormalForm(TSqlRegistry *reg)
{
   TClass *cl = 0;
   Version_t version = 0;
   if (!GetClassInfo(cl, version))
      return kFALSE;
   if (cl == 0)
      return kFALSE;

   TSQLClassInfo *sqlinfo = reg->fFile->RequestSQLClassInfo(cl->GetName(), version);

   TSQLTableData columns(reg->fFile, sqlinfo);
   // Bool_t needblob = kFALSE;

   TSqlRawBuffer rawdata(reg, sqlinfo);

   //   Int_t currrawid = 0;

   // add first column with object id
   columns.AddColumn(reg->fFile->SQLObjectIdColumn(), reg->fCurrentObjId);

   for (Int_t n = 0; n <= fChilds.GetLast(); n++) {
      TSQLStructure *child = (TSQLStructure *)fChilds.At(n);
      TStreamerElement *elem = child->GetElement();

      if (elem == 0) {
         Error("StoreClassInNormalForm", "CAN NOT BE");
         continue;
      }

      if (child->StoreElementInNormalForm(reg, &columns))
         continue;

      Int_t columntyp = DefineElementColumnType(elem, reg->fFile);
      if ((columntyp != kColRawData) && (columntyp != kColObjectArray)) {
         Error("StoreClassInNormalForm", "Element %s typ=%d has problem with normal store ", elem->GetName(),
               columntyp);
         continue;
      }

      Bool_t doblobs = kTRUE;

      Int_t blobid = rawdata.fRawId; // keep id of first raw, used in class table

      if (columntyp == kColObjectArray)
         if (child->TryConvertObjectArray(reg, &rawdata))
            doblobs = kFALSE;

      if (doblobs)
         child->PerformConversion(reg, &rawdata, elem->GetName(), kFALSE);

      if (blobid == rawdata.fRawId)
         blobid = -1; // no data for blob was created
      else {
         // reg->fFile->CreateRawTable(sqlinfo);
         // blobid = currrawid; // column will contain first raw id
         // reg->ConvertBlobs(&blobs, sqlinfo, currrawid);
         // needblob = kTRUE;
      }
      // blobs.Delete();

      TString blobname = elem->GetName();
      if (reg->fFile->GetUseSuffixes())
         blobname += sqlio::RawSuffix;

      columns.AddColumn(blobname, blobid);
   }

   reg->fFile->CreateClassTable(sqlinfo, columns.TakeColInfos());

   reg->InsertToNormalTable(&columns, sqlinfo);

   return kTRUE;
}

////////////////////////////////////////////////////////////////////////////////
/// produce string with complete index like [1][2][0]

TString TSQLStructure::MakeArrayIndex(TStreamerElement *elem, Int_t index)
{
   TString res;
   if ((elem == 0) || (elem->GetArrayLength() == 0))
      return res;

   for (Int_t ndim = elem->GetArrayDim() - 1; ndim >= 0; ndim--) {
      Int_t ix = index % elem->GetMaxIndex(ndim);
      index = index / elem->GetMaxIndex(ndim);
      TString buf;
      buf.Form("%s%d%s", "[", ix, "]");
      res = buf + res;
   }
   return res;
}

////////////////////////////////////////////////////////////////////////////////
/// tries to store element data in column

Bool_t TSQLStructure::StoreElementInNormalForm(TSqlRegistry *reg, TSQLTableData *columns)
{
   TStreamerElement *elem = GetElement();
   if (elem == 0)
      return kFALSE;

   Int_t typ = elem->GetType();

   Int_t columntyp = DefineElementColumnType(elem, reg->fFile);

   if (gDebug > 4)
      std::cout << "Element " << elem->GetName() << "   type = " << typ << "  column = " << columntyp << std::endl;

   TString colname = DefineElementColumnName(elem, reg->fFile);

   if (columntyp == kColTString) {
      const char *value;
      if (!RecognizeTString(value))
         return kFALSE;

      Int_t len = value ? strlen(value) : 0;

      Int_t sizelimit = reg->fFile->SQLSmallTextTypeLimit();

      const char *stype = reg->fFile->SQLSmallTextType();

      if (len <= sizelimit)
         columns->AddColumn(colname.Data(), stype, value, kFALSE);
      else {
         Int_t strid = reg->AddLongString(value);
         TString buf = reg->fFile->CodeLongString(reg->fCurrentObjId, strid);
         columns->AddColumn(colname.Data(), stype, buf.Data(), kFALSE);
      }

      return kTRUE;
   }

   if (columntyp == kColParent) {
      Long64_t objid = reg->fCurrentObjId;
      TClass *basecl = elem->GetClassPointer();
      Int_t resversion = basecl->GetClassVersion();
      if (!StoreObject(reg, objid, basecl, kFALSE))
         resversion = -1;
      columns->AddColumn(colname.Data(), resversion);
      return kTRUE;
   }

   if (columntyp == kColObject) {

      Long64_t objid = -1;

      if (NumChilds() == 1) {
         TSQLStructure *child = GetChild(0);

         if (child->GetType() == kSqlObject) {
            objid = child->DefineObjectId(kFALSE);
            if (!child->StoreObject(reg, objid, child->GetObjectClass()))
               return kFALSE;
         } else if (child->GetType() == kSqlPointer) {
            TString sobjid = child->GetValue();
            if (sobjid.Length() > 0)
               objid = sqlio::atol64(sobjid.Data());
         }
      }

      if (objid < 0) {
         // std::cout << "!!!! Not standard " << elem->GetName() << " class = " << elem->GetClassPointer()->GetName() <<
         // std::endl;
         objid = reg->GetNextObjId();
         if (!StoreObject(reg, objid, elem->GetClassPointer()))
            objid = -1; // this is a case, when no data was stored for this object
      }

      columns->AddColumn(colname.Data(), objid);
      return kTRUE;
   }

   if (columntyp == kColNormObject) {

      if (NumChilds() != 1) {
         Error("kColNormObject", "NumChilds()=%d", NumChilds());
         PrintLevel(20);
         return kFALSE;
      }
      TSQLStructure *child = GetChild(0);
      if ((child->GetType() != kSqlPointer) && (child->GetType() != kSqlObject))
         return kFALSE;

      Bool_t normal = kTRUE;

      Long64_t objid = -1;

      if (child->GetType() == kSqlObject) {
         objid = child->DefineObjectId(kFALSE);
         normal = child->StoreObject(reg, objid, child->GetObjectClass());
      } else {
         objid = child->DefineObjectId(kFALSE);
      }

      if (!normal) {
         Error("kColNormObject", "child->StoreObject fails");
         return kFALSE;
      }

      columns->AddColumn(colname.Data(), objid);
      return kTRUE;
   }

   if (columntyp == kColNormObjectArray) {

      if (elem->GetArrayLength() != NumChilds())
         return kFALSE;

      for (Int_t index = 0; index < NumChilds(); index++) {
         TSQLStructure *child = GetChild(index);
         if ((child->GetType() != kSqlPointer) && (child->GetType() != kSqlObject))
            return kFALSE;
         Bool_t normal = kTRUE;

         Long64_t objid = child->DefineObjectId(kFALSE);

         if (child->GetType() == kSqlObject)
            normal = child->StoreObject(reg, objid, child->GetObjectClass());

         if (!normal)
            return kFALSE;

         colname = DefineElementColumnName(elem, reg->fFile, index);

         columns->AddColumn(colname.Data(), objid);
      }
      return kTRUE;
   }

   if (columntyp == kColObjectPtr) {
      if (NumChilds() != 1)
         return kFALSE;
      TSQLStructure *child = GetChild(0);
      if ((child->GetType() != kSqlPointer) && (child->GetType() != kSqlObject))
         return kFALSE;

      Bool_t normal = kTRUE;
      Long64_t objid = -1;

      if (child->GetType() == kSqlObject) {
         objid = child->DefineObjectId(kFALSE);
         normal = child->StoreObject(reg, objid, child->GetObjectClass());
      }

      if (!normal)
         return kFALSE;

      columns->AddColumn(colname.Data(), objid);
      return kTRUE;
   }

   if (columntyp == kColSimple) {

      // only child shoud existing for element
      if (NumChilds() != 1) {
         Error("StoreElementInNormalForm", "Enexpected number %d for simple element %s", NumChilds(), elem->GetName());
         return kFALSE;
      }

      TSQLStructure *child = GetChild(0);
      if (child->GetType() != kSqlValue)
         return kFALSE;

      const char *value = child->GetValue();
      if (value == 0)
         return kFALSE;

      const char *sqltype = reg->fFile->SQLCompatibleType(typ);

      columns->AddColumn(colname.Data(), sqltype, value, IsNumericType(typ));

      return kTRUE;
   }

   if (columntyp == kColSimpleArray) {
      // number of items should be exactly equal to number of children

      if (NumChilds() != 1) {
         Error("StoreElementInNormalForm", "In fixed array %s only array node should be", elem->GetName());
         return kFALSE;
      }
      TSQLStructure *arr = GetChild(0);

      const char *sqltype = reg->fFile->SQLCompatibleType(typ % 20);

      for (Int_t n = 0; n < arr->NumChilds(); n++) {
         TSQLStructure *child = arr->GetChild(n);
         if (child->GetType() != kSqlValue)
            return kFALSE;

         const char *value = child->GetValue();
         if (value == 0)
            return kFALSE;

         Int_t index = child->GetArrayIndex();
         Int_t last = index + child->GetRepeatCounter();

         while (index < last) {
            colname = DefineElementColumnName(elem, reg->fFile, index);
            columns->AddColumn(colname.Data(), sqltype, value, kTRUE);
            index++;
         }
      }
      return kTRUE;
   }

   return kFALSE;
}

////////////////////////////////////////////////////////////////////////////////
/// tries to write array of objects as list of object references
/// in _streamer_ table, while objects itself will be stored in
/// other tables. If not successful, object data will be stored
/// in _streamer_ table

Bool_t TSQLStructure::TryConvertObjectArray(TSqlRegistry *reg, TSqlRawBuffer *blobs)
{
   TStreamerElement *elem = GetElement();
   if (elem == 0)
      return kFALSE;

   if (NumChilds() % 2 != 0)
      return kFALSE;

   Int_t indx = 0;

   while (indx < NumChilds()) {
      TSQLStructure *s_ver = GetChild(indx++);
      TSQLStructure *s_info = GetChild(indx++);
      if (!CheckNormalClassPair(s_ver, s_info))
         return kFALSE;
   }

   indx = 0;
   const char *ns = reg->fFile->SQLNameSeparator();

   while (indx < NumChilds() - 1) {
      indx++; // TSQLStructure* s_ver = GetChild(indx++);
      TSQLStructure *s_info = GetChild(indx++);
      TClass *cl = 0;
      Version_t version = 0;
      if (!s_info->GetClassInfo(cl, version))
         return kFALSE;
      Long64_t objid = reg->GetNextObjId();
      if (!s_info->StoreObject(reg, objid, cl))
         objid = -1; // this is a case, when no data was stored for this object

      TString sobjid;
      sobjid.Form("%lld", objid);

      blobs->AddLine(sqlio::ObjectRef_Arr, sobjid.Data(), elem->GetName(), ns);
   }

   return kTRUE;
}

////////////////////////////////////////////////////////////////////////////////
/// check if pair of two element corresponds
/// to start of object, stored in normal form

Bool_t TSQLStructure::CheckNormalClassPair(TSQLStructure *s_ver, TSQLStructure *s_info)
{
   if ((s_ver == 0) || (s_info == 0) || (s_ver->GetType() != kSqlVersion))
      return kFALSE;

   TClass *ver_cl = s_ver->GetVersionClass();

   TClass *info_cl = 0;
   Version_t info_ver = 0;
   if (!s_info->GetClassInfo(info_cl, info_ver))
      return kFALSE;

   if ((ver_cl == 0) || (info_cl == 0) || (ver_cl != info_cl) || (ver_cl->GetClassVersion() != info_ver))
      return kFALSE;

   return kTRUE;
}

////////////////////////////////////////////////////////////////////////////////
/// store data of TObject in special table
/// workaround custom TObject streamer

Bool_t TSQLStructure::StoreTObject(TSqlRegistry *reg)
{
   // check if it is really Looks like TObject data
   if ((NumChilds() < 3) || (NumChilds() > 4))
      return kFALSE;

   TSQLStructure *str_ver = GetChild(0);
   TSQLStructure *str_id = GetChild(1);
   TSQLStructure *str_bits = GetChild(2);
   TSQLStructure *str_prid = GetChild(3);

   if (str_ver->GetType() != kSqlVersion)
      return kFALSE;
   if ((str_id->GetType() != kSqlValue) || (str_id->GetValueType() != sqlio::UInt))
      return kFALSE;
   if ((str_bits->GetType() != kSqlValue) || (str_bits->GetValueType() != sqlio::UInt))
      return kFALSE;
   if (str_prid != 0)
      if ((str_prid->GetType() != kSqlValue) || (str_prid->GetValueType() != sqlio::UShort))
         return kFALSE;

   TSQLClassInfo *sqlinfo = reg->fFile->RequestSQLClassInfo(TObject::Class());

   if (sqlinfo == 0)
      return kFALSE;

   TSQLTableData columns(reg->fFile, sqlinfo);

   const char *uinttype = reg->fFile->SQLCompatibleType(TStreamerInfo::kUInt);

   columns.AddColumn(reg->fFile->SQLObjectIdColumn(), reg->fCurrentObjId);

   columns.AddColumn(sqlio::TObjectUniqueId, uinttype, str_id->GetValue(), kTRUE);
   columns.AddColumn(sqlio::TObjectBits, uinttype, str_bits->GetValue(), kTRUE);
   columns.AddColumn(sqlio::TObjectProcessId, "CHAR(3)", (str_prid ? str_prid->GetValue() : ""), kFALSE);

   reg->fFile->CreateClassTable(sqlinfo, columns.TakeColInfos());

   reg->InsertToNormalTable(&columns, sqlinfo);

   return kTRUE;
}

////////////////////////////////////////////////////////////////////////////////
/// store data of TString in special table
/// it is required when TString stored as pointer and reference to it possible

Bool_t TSQLStructure::StoreTString(TSqlRegistry *reg)
{
   const char *value = 0;
   if (!RecognizeTString(value))
      return kFALSE;

   TSQLClassInfo *sqlinfo = reg->fFile->RequestSQLClassInfo(TString::Class());
   if (sqlinfo == 0)
      return kFALSE;

   TSQLTableData columns(reg->fFile, sqlinfo);

   columns.AddColumn(reg->fFile->SQLObjectIdColumn(), reg->fCurrentObjId);
   columns.AddColumn(sqlio::TStringValue, reg->fFile->SQLBigTextType(), value, kFALSE);

   reg->fFile->CreateClassTable(sqlinfo, columns.TakeColInfos());

   reg->InsertToNormalTable(&columns, sqlinfo);
   return kTRUE;
}

////////////////////////////////////////////////////////////////////////////////
/// prove that structure contains TString data

Bool_t TSQLStructure::RecognizeTString(const char *&value)
{
   value = 0;

   if ((NumChilds() == 0) || (NumChilds() > 3))
      return kFALSE;

   TSQLStructure *len = 0, *lenbig = 0, *chars = 0;
   for (Int_t n = 0; n < NumChilds(); n++) {
      TSQLStructure *curr = GetChild(n);
      if (curr->fType != kSqlValue)
         return kFALSE;
      if (curr->fPointer == sqlio::UChar) {
         if (len == 0)
            len = curr;
         else
            return kFALSE;
      } else if (curr->fPointer == sqlio::Int) {
         if (lenbig == 0)
            lenbig = curr;
         else
            return kFALSE;
      } else if (curr->fPointer == sqlio::CharStar) {
         if (chars == 0)
            chars = curr;
         else
            return kFALSE;
      } else
         return kFALSE;
   }

   if (len == 0)
      return kFALSE;
   if ((lenbig != 0) && ((chars == 0) || (len == 0)))
      return kFALSE;

   if (chars != 0)
      value = chars->GetValue();

   return kTRUE;
}

////////////////////////////////////////////////////////////////////////////////
/// defines which kind of column can be assigned for this element
/// Possible cases
///    kColSimple       -  basic data type
///    kColSimpleArray  -  fixed array of basic types
///    kColParent       -  parent class
///    kColObject       -  object as data member
///    kColObjectPtr    -  object as pointer
///    kColTString      -  TString
///    kColRawData      -  anything else as raw data

Int_t TSQLStructure::DefineElementColumnType(TStreamerElement *elem, TSQLFile *f)
{
   if (elem == 0)
      return kColUnknown;

   Int_t typ = elem->GetType();

   if (typ == TStreamerInfo::kMissing)
      return kColRawData;

   if ((typ > 0) && (typ < 20) && (typ != TStreamerInfo::kCharStar))
      return kColSimple;

   if ((typ > TStreamerInfo::kOffsetL) && (typ < TStreamerInfo::kOffsetP))
      if ((f->GetArrayLimit() < 0) || (elem->GetArrayLength() <= f->GetArrayLimit()))
         return kColSimpleArray;

   if (typ == TStreamerInfo::kTObject) {
      if (elem->InheritsFrom(TStreamerBase::Class()))
         return kColParent;
      else
         return kColObject;
   }

   if (typ == TStreamerInfo::kTNamed) {
      if (elem->InheritsFrom(TStreamerBase::Class()))
         return kColParent;
      else
         return kColObject;
   }

   if (typ == TStreamerInfo::kTString)
      return kColTString;

   if (typ == TStreamerInfo::kBase)
      return kColParent;

   if (typ == TStreamerInfo::kSTL)
      if (elem->InheritsFrom(TStreamerBase::Class()))
         return kColParent;

   // this is workaround
   // these two tags stored with WriteFastArray, but read with cl->Streamer()
   if ((typ == TStreamerInfo::kObject) || (typ == TStreamerInfo::kAny)) {
      if (elem->GetArrayLength() == 0)
         return kColObject;
      else if (elem->GetStreamer() == 0)
         return kColObjectArray;
   }

   if ((typ == TStreamerInfo::kObject) || (typ == TStreamerInfo::kAny) || (typ == TStreamerInfo::kAnyp) ||
       (typ == TStreamerInfo::kObjectp) || (typ == TStreamerInfo::kAnyP) || (typ == TStreamerInfo::kObjectP)) {
      if ((elem->GetArrayLength() == 0) || (elem->GetStreamer() != 0))
         return kColNormObject;
      else
         return kColNormObjectArray;
   }

   if ((typ == TStreamerInfo::kObject + TStreamerInfo::kOffsetL) ||
       (typ == TStreamerInfo::kAny + TStreamerInfo::kOffsetL) ||
       (typ == TStreamerInfo::kAnyp + TStreamerInfo::kOffsetL) ||
       (typ == TStreamerInfo::kObjectp + TStreamerInfo::kOffsetL) ||
       (typ == TStreamerInfo::kAnyP + TStreamerInfo::kOffsetL) ||
       (typ == TStreamerInfo::kObjectP + TStreamerInfo::kOffsetL)) {
      if (elem->GetStreamer() != 0)
         return kColNormObject;
      else
         return kColNormObjectArray;
   }

   if ((typ == TStreamerInfo::kObject) || (typ == TStreamerInfo::kAny) || (typ == TStreamerInfo::kAnyp) ||
       (typ == TStreamerInfo::kObjectp) || (typ == TStreamerInfo::kSTL)) {
      if (elem->GetArrayLength() == 0)
         return kColObject;
      else if (elem->GetStreamer() == 0)
         return kColObjectArray;
   }

   if (((typ == TStreamerInfo::kAnyP) || (typ == TStreamerInfo::kObjectP)) && (elem->GetArrayDim() == 0))
      return kColObjectPtr;

   //   if ((typ==TStreamerInfo::kSTLp) &&
   //       (elem->GetArrayDim()==0)) {
   //      TStreamerSTL* stl = dynamic_cast<TStreamerSTL*> (elem);
   //      if ((stl!=0) && (dynamic_cast<TStreamerSTLstring*>(elem)==0))
   //        return kColObjectPtr;
   //   }

   return kColRawData;
}

////////////////////////////////////////////////////////////////////////////////
/// returns name of the column in class table for that element

TString TSQLStructure::DefineElementColumnName(TStreamerElement *elem, TSQLFile *f, Int_t indx)
{
   TString colname = "";

   Int_t coltype = DefineElementColumnType(elem, f);
   if (coltype == kColUnknown)
      return colname;

   const char *elemname = elem->GetName();

   switch (coltype) {
   case kColSimple: {
      colname = elemname;
      if (f->GetUseSuffixes()) {
         colname += f->SQLNameSeparator();
         colname += GetSimpleTypeName(elem->GetType());
      }
      break;
   }

   case kColSimpleArray: {
      colname = elemname;
      colname += MakeArrayIndex(elem, indx);
      break;
   }

   case kColParent: {
      colname = elemname;
      if (f->GetUseSuffixes())
         colname += sqlio::ParentSuffix;
      break;
   }

   case kColNormObject: {
      colname = elemname;
      if (f->GetUseSuffixes())
         colname += sqlio::ObjectSuffix;
      break;
   }

   case kColNormObjectArray: {
      colname = elemname;
      colname += MakeArrayIndex(elem, indx);
      if (f->GetUseSuffixes())
         colname += sqlio::ObjectSuffix;
      break;
   }

   case kColObject: {
      colname = elemname;
      if (f->GetUseSuffixes())
         colname += sqlio::ObjectSuffix;
      break;
   }

   case kColObjectPtr: {
      colname = elemname;
      if (f->GetUseSuffixes())
         colname += sqlio::PointerSuffix;
      break;
   }

   case kColTString: {
      colname = elem->GetName();
      if (f->GetUseSuffixes())
         colname += sqlio::StrSuffix;
      break;
   }

   case kColRawData: {
      colname = elemname;
      if (f->GetUseSuffixes())
         colname += sqlio::RawSuffix;
      break;
   }

   case kColObjectArray: {
      colname = elemname;
      if (f->GetUseSuffixes())
         colname += sqlio::RawSuffix;
      break;
   }
   }

   return colname;
}

////////////////////////////////////////////////////////////////////////////////
/// find column in TSQLObjectData object, which correspond to current element

Int_t TSQLStructure::LocateElementColumn(TSQLFile *f, TBufferSQL2 *buf, TSQLObjectData *data)
{
   TStreamerElement *elem = GetElement();
   if ((elem == 0) || (data == 0))
      return kColUnknown;

   Int_t coltype = DefineElementColumnType(elem, f);

   if (gDebug > 4)
      std::cout << "TSQLStructure::LocateElementColumn " << elem->GetName() << " coltyp = " << coltype << " : "
                << elem->GetType() << " len = " << elem->GetArrayLength() << std::endl;

   if (coltype == kColUnknown)
      return kColUnknown;

   const char *elemname = elem->GetName();
   Bool_t located = kFALSE;

   TString colname = DefineElementColumnName(elem, f);

   if (gDebug > 4)
      std::cout << "         colname = " << colname << " in " << data->GetInfo()->GetClassTableName() << std::endl;

   switch (coltype) {
   case kColSimple: {
      located = data->LocateColumn(colname.Data());
      break;
   }

   case kColSimpleArray: {
      located = data->LocateColumn(colname);
      break;
   }

   case kColParent: {
      located = data->LocateColumn(colname.Data());
      if (located == kColUnknown)
         return kColUnknown;

      Long64_t objid = DefineObjectId(kTRUE);
      const char *clname = elemname;
      Version_t version = atoi(data->GetValue());

      // this is a case, when parent store nothing in the database
      if (version < 0)
         break;

      // special treatment for TObject
      if (strcmp(clname, TObject::Class()->GetName()) == 0) {
         UnpackTObject(f, buf, data, objid, version);
         break;
      }

      TSQLClassInfo *sqlinfo = f->FindSQLClassInfo(clname, version);
      if (sqlinfo == 0)
         return kColUnknown;

      // this will indicate that streamer is completely custom
      if (sqlinfo->IsClassTableExist()) {
         data->AddUnpackInt(sqlio::Version, version);
      } else {
         TSQLObjectData *objdata = buf->SqlObjectData(objid, sqlinfo);
         if ((objdata == 0) || !objdata->PrepareForRawData())
            return kColUnknown;
         AddObjectData(objdata);
      }

      break;
   }

   // This is a case when streamer of object will be called directly.
   // Typically it happens when object is data member of the class.
   // Here we need to define class of object and if it was written by
   // normal streamer (via TStreamerInfo methods) or directly as blob.
   // When blob was used, blob data should be read.
   // In normal case only version is required. Other object data will be
   // read by TBufferSQL2::IncrementLevel method
   case kColObject: {
      located = data->LocateColumn(colname.Data());
      if (located == kColUnknown)
         return located;

      const char *strobjid = data->GetValue();
      if (strobjid == 0)
         return kColUnknown;

      Long64_t objid = sqlio::atol64(strobjid);

      // when nothing was stored, nothing need to be read. skip
      if (objid < 0)
         break;

      TString clname;
      Version_t version;

      if (!buf->SqlObjectInfo(objid, clname, version))
         return kColUnknown;

      // special treatment for TObject
      if (clname == TObject::Class()->GetName()) {
         UnpackTObject(f, buf, data, objid, version);
         break;
      }

      TSQLClassInfo *sqlinfo = f->FindSQLClassInfo(clname.Data(), version);
      if (sqlinfo == 0)
         return kColUnknown;

      if (sqlinfo->IsClassTableExist()) {
         data->AddUnpackInt(sqlio::Version, version);
      } else {
         TSQLObjectData *objdata = buf->SqlObjectData(objid, sqlinfo);
         if ((objdata == 0) || !objdata->PrepareForRawData())
            return kColUnknown;
         AddObjectData(objdata);
      }

      // work around to store objid of object, which is memeber of class
      fValue = strobjid;

      break;
   }

   // this is case of pointer on any object
   // field contains objectid.
   // Object id, class of object and so on will be checked
   // when TBuffer::ReadObject method will be called
   case kColObjectPtr: {
      located = data->LocateColumn(colname.Data());
      break;
   }

   // this is case of on object which is treated normally in TBuffer
   // field should contains objectid.
   // Object id, class of object and so on will be checked
   // when TBuffer::StreamObject method will be called
   case kColNormObject: {
      located = data->LocateColumn(colname.Data());
      break;
   }

   case kColNormObjectArray: {
      located = data->LocateColumn(colname.Data());
      break;
   }

   case kColTString: {
      located = data->LocateColumn(colname);
      if (located == kColUnknown)
         return located;
      const char *value = data->GetValue();

      Long64_t objid = DefineObjectId(kTRUE);
      Int_t strid = f->IsLongStringCode(objid, value);

      TString buf2;

      // if special prefix found, than try get such string
      if (strid > 0)
         if (f->GetLongString(objid, strid, buf2))
            value = buf2.Data();

      Int_t len = (value == 0) ? 0 : strlen(value);
      if (len < 255) {
         data->AddUnpackInt(sqlio::UChar, len);
      } else {
         data->AddUnpackInt(sqlio::UChar, 255);
         data->AddUnpackInt(sqlio::Int, len);
      }
      if (len > 0)
         data->AddUnpack(sqlio::CharStar, value);
      break;
   }

   case kColRawData: {
      located = data->LocateColumn(colname.Data(), kTRUE);
      break;
   }

   case kColObjectArray: {
      located = data->LocateColumn(colname.Data(), kTRUE);
      break;
   }
   }

   if (!located)
      coltype = kColUnknown;

   return coltype;
}

////////////////////////////////////////////////////////////////////////////////
/// Unpack TObject data in form, accepted by custom TObject streamer

Bool_t
TSQLStructure::UnpackTObject(TSQLFile *f, TBufferSQL2 *buf, TSQLObjectData *data, Long64_t objid, Int_t clversion)
{
   TSQLClassInfo *sqlinfo = f->FindSQLClassInfo(TObject::Class()->GetName(), clversion);
   if (sqlinfo == 0)
      return kFALSE;

   TSQLObjectData *tobjdata = buf->SqlObjectData(objid, sqlinfo);
   if (tobjdata == 0)
      return kFALSE;

   data->AddUnpackInt(sqlio::Version, clversion);

   tobjdata->LocateColumn(sqlio::TObjectUniqueId);
   data->AddUnpack(sqlio::UInt, tobjdata->GetValue());
   tobjdata->ShiftToNextValue();

   tobjdata->LocateColumn(sqlio::TObjectBits);
   data->AddUnpack(sqlio::UInt, tobjdata->GetValue());
   tobjdata->ShiftToNextValue();

   tobjdata->LocateColumn(sqlio::TObjectProcessId);
   const char *value = tobjdata->GetValue();
   if ((value != 0) && (strlen(value) > 0))
      data->AddUnpack(sqlio::UShort, value);

   delete tobjdata;

   return kTRUE;
}

////////////////////////////////////////////////////////////////////////////////
/// Unpack TString data in form, accepted by custom TString streamer

Bool_t
TSQLStructure::UnpackTString(TSQLFile *f, TBufferSQL2 *buf, TSQLObjectData *data, Long64_t objid, Int_t clversion)
{
   TSQLClassInfo *sqlinfo = f->FindSQLClassInfo(TString::Class()->GetName(), clversion);
   if (sqlinfo == 0)
      return kFALSE;

   TSQLObjectData *tstringdata = buf->SqlObjectData(objid, sqlinfo);
   if (tstringdata == 0)
      return kFALSE;

   tstringdata->LocateColumn(sqlio::TStringValue);

   const char *value = tstringdata->GetValue();

   Int_t len = (value == 0) ? 0 : strlen(value);
   if (len < 255) {
      data->AddUnpackInt(sqlio::UChar, len);
   } else {
      data->AddUnpackInt(sqlio::UChar, 255);
      data->AddUnpackInt(sqlio::Int, len);
   }
   if (len > 0)
      data->AddUnpack(sqlio::CharStar, value);

   delete tstringdata;

   return kTRUE;
}

////////////////////////////////////////////////////////////////////////////////
/// adds quotes around string value and replaces some special symbols

void TSQLStructure::AddStrBrackets(TString &s, const char *quote)
{
   if (strcmp(quote, "\"") == 0)
      s.ReplaceAll("\"", "\\\"");
   else
      s.ReplaceAll("'", "''");
   s.Prepend(quote);
   s.Append(quote);
}