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fcl-db: odbc: implements RefreshLastInsertID for autoincrementing columns.

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Bug #16076

git-svn-id: trunk@29751 -
This commit is contained in:
lacak 2015-02-18 11:02:07 +00:00
parent a861bbc5ae
commit 2a2078e7f7
2 changed files with 240 additions and 203 deletions
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433
packages/fcl-db/src/sqldb/odbc/odbcconn.pas
View File

@ -56,10 +56,16 @@ type
TODBCConnection = class(TSQLConnection) TODBCConnection = class(TSQLConnection)
private private
type
TDBMSInfo = record
GetLastInsertIDSQL: string; // SQL statement for get last insert value for autoincrement column
end;
var
FDriver: string; FDriver: string;
FEnvironment:TODBCEnvironment; FEnvironment:TODBCEnvironment;
FDBCHandle:SQLHDBC; // ODBC Connection Handle FDBCHandle:SQLHDBC; // ODBC Connection Handle
FFileDSN: string; FFileDSN: string;
FDBMSInfo: TDBMSInfo;
procedure SetParameters(ODBCCursor:TODBCCursor; AParams:TParams); procedure SetParameters(ODBCCursor:TODBCCursor; AParams:TParams);
procedure FreeParamBuffers(ODBCCursor:TODBCCursor); procedure FreeParamBuffers(ODBCCursor:TODBCCursor);
@ -87,6 +93,7 @@ type
// - Statement execution // - Statement execution
procedure Execute(cursor:TSQLCursor; ATransaction:TSQLTransaction; AParams:TParams); override; procedure Execute(cursor:TSQLCursor; ATransaction:TSQLTransaction; AParams:TParams); override;
function RowsAffected(cursor: TSQLCursor): TRowsCount; override; function RowsAffected(cursor: TSQLCursor): TRowsCount; override;
function RefreshLastInsertID(Query : TCustomSQLQuery; Field : TField): boolean; override;
// - Result retrieving // - Result retrieving
procedure AddFieldDefs(cursor:TSQLCursor; FieldDefs:TFieldDefs); override; procedure AddFieldDefs(cursor:TSQLCursor; FieldDefs:TFieldDefs); override;
function Fetch(cursor:TSQLCursor):boolean; override; function Fetch(cursor:TSQLCursor):boolean; override;
@ -545,6 +552,7 @@ var
ConnectionString:string; ConnectionString:string;
OutConnectionString:string; OutConnectionString:string;
ActualLength:SQLSMALLINT; ActualLength:SQLSMALLINT;
DBMS_NAME: array[0..20] of AnsiChar;
begin begin
// Do not call the inherited method as it checks for a non-empty DatabaseName, and we don't even use DatabaseName! // Do not call the inherited method as it checks for a non-empty DatabaseName, and we don't even use DatabaseName!
// inherited DoInternalConnect; // inherited DoInternalConnect;
@ -589,9 +597,24 @@ begin
end; end;
end; end;
// commented out as the OutConnectionString is not used further at the moment // set DBMS specific options
// if ActualLength<BufferLength-1 then if SQLGetInfo(FDBCHandle, SQL_DBMS_NAME, @DBMS_NAME, sizeof(DBMS_NAME), @ActualLength) = SQL_SUCCESS then
// SetLength(OutConnectionString,ActualLength); // fix completed connection string length case AnsiString(DBMS_NAME) of
'Microsoft SQL Server':
begin
FDBMSInfo.GetLastInsertIDSQL := 'SELECT @@IDENTITY';
Include(FConnOptions, sqLastInsertID);
end;
'MySQL':
begin
FDBMSInfo.GetLastInsertIDSQL := 'SELECT last_insert_id()';
Include(FConnOptions, sqLastInsertID);
end;
else
begin
FDBMSInfo.GetLastInsertIDSQL := '';
end;
end;
// set connection attributes (none yet) // set connection attributes (none yet)
end; end;
@ -779,204 +802,20 @@ begin
Result:=-1; Result:=-1;
end; end;
function TODBCConnection.Fetch(cursor: TSQLCursor): boolean; function TODBCConnection.RefreshLastInsertID(Query : TCustomSQLQuery; Field : TField): boolean;
var var
ODBCCursor:TODBCCursor; STMTHandle: SQLHSTMT;
Res:SQLRETURN; StrLenOrInd: SQLLEN;
LastInsertID: LargeInt;
begin begin
ODBCCursor:=cursor as TODBCCursor; if SQLAllocHandle(SQL_HANDLE_STMT, FDBCHandle, STMTHandle) = SQL_SUCCESS then
// fetch new row
Res:=SQLFetch(ODBCCursor.FSTMTHandle);
if Res<>SQL_NO_DATA then
ODBCCheckResult(Res,SQL_HANDLE_STMT, ODBCCursor.FSTMTHandle, 'Could not fetch new row from result set.');
// result is true iff a new row was available
Result:=Res<>SQL_NO_DATA;
end;
const
DEFAULT_BLOB_BUFFER_SIZE = 1024;
function TODBCConnection.LoadField(cursor: TSQLCursor; FieldDef: TFieldDef; buffer: pointer; out CreateBlob : boolean): boolean;
var
ODBCCursor:TODBCCursor;
StrLenOrInd:SQLLEN;
ODBCDateStruct:SQL_DATE_STRUCT;
ODBCTimeStruct:SQL_TIME_STRUCT;
ODBCTimeStampStruct:SQL_TIMESTAMP_STRUCT;
DateTime:TDateTime;
Res:SQLRETURN;
begin
CreateBlob := False;
ODBCCursor:=cursor as TODBCCursor;
// load the field using SQLGetData
// Note: optionally we can implement the use of SQLBindCol later for even more speed
// TODO: finish this
case FieldDef.DataType of
ftWideString,ftFixedWideChar: // mapped to TWideStringField
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_WCHAR, buffer, FieldDef.Size+sizeof(WideChar), @StrLenOrInd); //buffer must contain space for the null-termination character
ftGuid, ftFixedChar,ftString: // are mapped to a TStringField (including TGuidField)
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_CHAR, buffer, FieldDef.Size+1, @StrLenOrInd);
ftSmallint: // mapped to TSmallintField
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_SSHORT, buffer, SizeOf(Smallint), @StrLenOrInd);
ftInteger,ftAutoInc: // mapped to TLongintField
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_SLONG, buffer, SizeOf(Longint), @StrLenOrInd);
ftWord: // mapped to TWordField
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_USHORT, buffer, SizeOf(Word), @StrLenOrInd);
ftLargeint: // mapped to TLargeintField
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_SBIGINT, buffer, SizeOf(Largeint), @StrLenOrInd);
ftFloat,ftCurrency: // mapped to TFloatField
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_DOUBLE, buffer, SizeOf(Double), @StrLenOrInd);
ftTime: // mapped to TTimeField
begin begin
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_TYPE_TIME, @ODBCTimeStruct, SizeOf(SQL_TIME_STRUCT), @StrLenOrInd); if SQLExecDirect(STMTHandle, PChar(FDBMSInfo.GetLastInsertIDSQL), Length(FDBMSInfo.GetLastInsertIDSQL)) = SQL_SUCCESS then
if StrLenOrInd<>SQL_NULL_DATA then if SQLFetch(STMTHandle) = SQL_SUCCESS then
begin if SQLGetData(STMTHandle, 1, SQL_C_SBIGINT, @LastInsertID, SizeOf(LargeInt), @StrLenOrInd) = SQL_SUCCESS then
DateTime:=TimeStructToDateTime(@ODBCTimeStruct); Field.AsLargeInt := LastInsertID;
Move(DateTime, buffer^, SizeOf(TDateTime)); SQLFreeHandle(SQL_HANDLE_STMT, STMTHandle);
end; end;
end;
ftDate: // mapped to TDateField
begin
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_TYPE_DATE, @ODBCDateStruct, SizeOf(SQL_DATE_STRUCT), @StrLenOrInd);
if StrLenOrInd<>SQL_NULL_DATA then
begin
DateTime:=DateStructToDateTime(@ODBCDateStruct);
Move(DateTime, buffer^, SizeOf(TDateTime));
end;
end;
ftDateTime: // mapped to TDateTimeField
begin
// Seems like not all ODBC-drivers (mysql on Linux) set the fractional part. Initialize
// it's value to avoid 'random' data.
ODBCTimeStampStruct.Fraction:=0;
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_TYPE_TIMESTAMP, @ODBCTimeStampStruct, SizeOf(SQL_TIMESTAMP_STRUCT), @StrLenOrInd);
if StrLenOrInd<>SQL_NULL_DATA then
begin
DateTime:=TimeStampStructToDateTime(@ODBCTimeStampStruct);
Move(DateTime, buffer^, SizeOf(TDateTime));
end;
end;
ftBoolean: // mapped to TBooleanField
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_BIT, buffer, SizeOf(Wordbool), @StrLenOrInd);
ftBytes: // mapped to TBytesField
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_BINARY, buffer, FieldDef.Size, @StrLenOrInd);
ftVarBytes: // mapped to TVarBytesField
begin
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_BINARY, buffer+SizeOf(Word), FieldDef.Size, @StrLenOrInd);
if StrLenOrInd < 0 then
PWord(buffer)^ := 0
else
PWord(buffer)^ := StrLenOrInd;
end;
ftWideMemo,
ftBlob, ftMemo: // BLOBs
begin
//Writeln('BLOB');
// Try to discover BLOB data length
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_BINARY, buffer, 0, @StrLenOrInd);
ODBCCheckResult(Res, SQL_HANDLE_STMT, ODBCCursor.FSTMTHandle, 'Could not get field data for field "%s" (index %d).',[FieldDef.Name, FieldDef.Index+1]);
// Read the data if not NULL
if StrLenOrInd<>SQL_NULL_DATA then
begin
CreateBlob:=true; // defer actual loading of blob data to LoadBlobIntoBuffer method
//WriteLn('Deferring loading of blob of length ',StrLenOrInd);
end;
end;
// TODO: Loading of other field types
else
raise EODBCException.CreateFmt('Tried to load field of unsupported field type %s',[Fieldtypenames[FieldDef.DataType]]);
end;
ODBCCheckResult(Res, SQL_HANDLE_STMT, ODBCCursor.FSTMTHandle, 'Could not get field data for field "%s" (index %d).',[FieldDef.Name, FieldDef.Index+1]);
Result:=StrLenOrInd<>SQL_NULL_DATA; // Result indicates whether the value is non-null
//writeln(Format('Field.Size: %d; StrLenOrInd: %d',[FieldDef.Size, StrLenOrInd]));
end;
procedure TODBCConnection.LoadBlobIntoBuffer(FieldDef: TFieldDef; ABlobBuf: PBufBlobField; cursor: TSQLCursor; ATransaction: TSQLTransaction);
var
ODBCCursor: TODBCCursor;
Res: SQLRETURN;
StrLenOrInd:SQLLEN;
BlobBuffer:pointer;
BlobBufferSize,BytesRead:SQLINTEGER;
BlobMemoryStream:TMemoryStream;
begin
ODBCCursor:=cursor as TODBCCursor;
// Try to discover BLOB data length
// NB MS ODBC requires that TargetValuePtr is not nil, so we supply it with a valid pointer, even though BufferLength is 0
StrLenOrInd:=0;
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_BINARY, @BlobBuffer, 0, @StrLenOrInd);
if Res<>SQL_NO_DATA then
ODBCCheckResult(Res, SQL_HANDLE_STMT, ODBCCursor.FSTMTHandle, 'Could not get field data for field "%s" (index %d).',[FieldDef.Name, FieldDef.Index+1]);
// Read the data if not NULL
if StrLenOrInd<>SQL_NULL_DATA then
begin
// Determine size of buffer to use
if StrLenOrInd<>SQL_NO_TOTAL then begin
// Size is known on beforehand
// set size & alloc buffer
//WriteLn('Loading blob of length ',StrLenOrInd);
BlobBufferSize:=StrLenOrInd;
ABlobBuf^.BlobBuffer^.Size:=BlobBufferSize;
ReAllocMem(ABlobBuf^.BlobBuffer^.Buffer, BlobBufferSize);
// get blob data
if BlobBufferSize>0 then begin
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_BINARY, ABlobBuf^.BlobBuffer^.Buffer, BlobBufferSize, @StrLenOrInd);
ODBCCheckResult(Res, SQL_HANDLE_STMT, ODBCCursor.FSTMTHandle, 'Could not load blob data for field "%s" (index %d).',[FieldDef.Name, FieldDef.Index+1]);
end;
end else begin
// Size is not known on beforehand; read data in chuncks; write to a TMemoryStream (which implements O(n) writing)
BlobBufferSize:=DEFAULT_BLOB_BUFFER_SIZE;
// init BlobBuffer and BlobMemoryStream to nil pointers
BlobBuffer:=nil; // the buffer that will hold the chuncks of data; not to be confused with ABlobBuf^.BlobBuffer
BlobMemoryStream:=nil;
try
// Allocate the buffer and memorystream
BlobBuffer:=GetMem(BlobBufferSize);
BlobMemoryStream:=TMemoryStream.Create;
// Retrieve data in parts
repeat
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_BINARY, BlobBuffer, BlobBufferSize, @StrLenOrInd);
ODBCCheckResult(Res, SQL_HANDLE_STMT, ODBCCursor.FSTMTHandle, 'Could not load (partial) blob data for field "%s" (index %d).',[FieldDef.Name, FieldDef.Index+1]);
// Append data in buffer to memorystream
if (StrLenOrInd=SQL_NO_TOTAL) or (StrLenOrInd>BlobBufferSize) then
BytesRead:=BlobBufferSize
else
BytesRead:=StrLenOrInd;
BlobMemoryStream.Write(BlobBuffer^, BytesRead);
until Res=SQL_SUCCESS;
// Copy memory stream data to ABlobBuf^.BlobBuffer
BlobBufferSize:=BlobMemoryStream.Size; // actual blob size
// alloc ABlobBuf^.BlobBuffer
ABlobBuf^.BlobBuffer^.Size:=BlobBufferSize;
ReAllocMem(ABlobBuf^.BlobBuffer^.Buffer, BlobBufferSize);
// read memory stream data into ABlobBuf^.BlobBuffer
BlobMemoryStream.Position:=0;
BlobMemoryStream.Read(ABlobBuf^.BlobBuffer^.Buffer^, BlobBufferSize);
finally
// free buffer and memory stream
BlobMemoryStream.Free;
if BlobBuffer<>nil then
Freemem(BlobBuffer,BlobBufferSize);
end;
end;
end;
end;
procedure TODBCConnection.FreeFldBuffers(cursor: TSQLCursor);
var
ODBCCursor:TODBCCursor;
begin
ODBCCursor:=cursor as TODBCCursor;
if ODBCCursor.FSTMTHandle <> SQL_NULL_HSTMT then
ODBCCheckResult(
SQLFreeStmt(ODBCCursor.FSTMTHandle, SQL_CLOSE),
SQL_HANDLE_STMT, ODBCCursor.FSTMTHandle, 'Could not close ODBC statement cursor.'
);
end; end;
procedure TODBCConnection.AddFieldDefs(cursor: TSQLCursor; FieldDefs: TFieldDefs); procedure TODBCConnection.AddFieldDefs(cursor: TSQLCursor; FieldDefs: TFieldDefs);
@ -1202,6 +1041,206 @@ begin
end; end;
end; end;
function TODBCConnection.Fetch(cursor: TSQLCursor): boolean;
var
ODBCCursor:TODBCCursor;
Res:SQLRETURN;
begin
ODBCCursor:=cursor as TODBCCursor;
// fetch new row
Res:=SQLFetch(ODBCCursor.FSTMTHandle);
if Res<>SQL_NO_DATA then
ODBCCheckResult(Res,SQL_HANDLE_STMT, ODBCCursor.FSTMTHandle, 'Could not fetch new row from result set.');
// result is true iff a new row was available
Result:=Res<>SQL_NO_DATA;
end;
const
DEFAULT_BLOB_BUFFER_SIZE = 1024;
function TODBCConnection.LoadField(cursor: TSQLCursor; FieldDef: TFieldDef; buffer: pointer; out CreateBlob : boolean): boolean;
var
ODBCCursor:TODBCCursor;
StrLenOrInd:SQLLEN;
ODBCDateStruct:SQL_DATE_STRUCT;
ODBCTimeStruct:SQL_TIME_STRUCT;
ODBCTimeStampStruct:SQL_TIMESTAMP_STRUCT;
DateTime:TDateTime;
Res:SQLRETURN;
begin
CreateBlob := False;
ODBCCursor:=cursor as TODBCCursor;
// load the field using SQLGetData
// Note: optionally we can implement the use of SQLBindCol later for even more speed
// TODO: finish this
case FieldDef.DataType of
ftWideString,ftFixedWideChar: // mapped to TWideStringField
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_WCHAR, buffer, FieldDef.Size+sizeof(WideChar), @StrLenOrInd); //buffer must contain space for the null-termination character
ftGuid, ftFixedChar,ftString: // are mapped to a TStringField (including TGuidField)
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_CHAR, buffer, FieldDef.Size+1, @StrLenOrInd);
ftSmallint: // mapped to TSmallintField
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_SSHORT, buffer, SizeOf(Smallint), @StrLenOrInd);
ftInteger,ftAutoInc: // mapped to TLongintField
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_SLONG, buffer, SizeOf(Longint), @StrLenOrInd);
ftWord: // mapped to TWordField
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_USHORT, buffer, SizeOf(Word), @StrLenOrInd);
ftLargeint: // mapped to TLargeintField
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_SBIGINT, buffer, SizeOf(Largeint), @StrLenOrInd);
ftFloat,ftCurrency: // mapped to TFloatField
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_DOUBLE, buffer, SizeOf(Double), @StrLenOrInd);
ftTime: // mapped to TTimeField
begin
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_TYPE_TIME, @ODBCTimeStruct, SizeOf(SQL_TIME_STRUCT), @StrLenOrInd);
if StrLenOrInd<>SQL_NULL_DATA then
begin
DateTime:=TimeStructToDateTime(@ODBCTimeStruct);
Move(DateTime, buffer^, SizeOf(TDateTime));
end;
end;
ftDate: // mapped to TDateField
begin
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_TYPE_DATE, @ODBCDateStruct, SizeOf(SQL_DATE_STRUCT), @StrLenOrInd);
if StrLenOrInd<>SQL_NULL_DATA then
begin
DateTime:=DateStructToDateTime(@ODBCDateStruct);
Move(DateTime, buffer^, SizeOf(TDateTime));
end;
end;
ftDateTime: // mapped to TDateTimeField
begin
// Seems like not all ODBC-drivers (mysql on Linux) set the fractional part. Initialize
// it's value to avoid 'random' data.
ODBCTimeStampStruct.Fraction:=0;
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_TYPE_TIMESTAMP, @ODBCTimeStampStruct, SizeOf(SQL_TIMESTAMP_STRUCT), @StrLenOrInd);
if StrLenOrInd<>SQL_NULL_DATA then
begin
DateTime:=TimeStampStructToDateTime(@ODBCTimeStampStruct);
Move(DateTime, buffer^, SizeOf(TDateTime));
end;
end;
ftBoolean: // mapped to TBooleanField
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_BIT, buffer, SizeOf(Wordbool), @StrLenOrInd);
ftBytes: // mapped to TBytesField
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_BINARY, buffer, FieldDef.Size, @StrLenOrInd);
ftVarBytes: // mapped to TVarBytesField
begin
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_BINARY, buffer+SizeOf(Word), FieldDef.Size, @StrLenOrInd);
if StrLenOrInd < 0 then
PWord(buffer)^ := 0
else
PWord(buffer)^ := StrLenOrInd;
end;
ftWideMemo,
ftBlob, ftMemo: // BLOBs
begin
//Writeln('BLOB');
// Try to discover BLOB data length
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_BINARY, buffer, 0, @StrLenOrInd);
ODBCCheckResult(Res, SQL_HANDLE_STMT, ODBCCursor.FSTMTHandle, 'Could not get field data for field "%s" (index %d).',[FieldDef.Name, FieldDef.Index+1]);
// Read the data if not NULL
if StrLenOrInd<>SQL_NULL_DATA then
begin
CreateBlob:=true; // defer actual loading of blob data to LoadBlobIntoBuffer method
//WriteLn('Deferring loading of blob of length ',StrLenOrInd);
end;
end;
// TODO: Loading of other field types
else
raise EODBCException.CreateFmt('Tried to load field of unsupported field type %s',[Fieldtypenames[FieldDef.DataType]]);
end;
ODBCCheckResult(Res, SQL_HANDLE_STMT, ODBCCursor.FSTMTHandle, 'Could not get field data for field "%s" (index %d).',[FieldDef.Name, FieldDef.Index+1]);
Result:=StrLenOrInd<>SQL_NULL_DATA; // Result indicates whether the value is non-null
//writeln(Format('Field.Size: %d; StrLenOrInd: %d',[FieldDef.Size, StrLenOrInd]));
end;
procedure TODBCConnection.LoadBlobIntoBuffer(FieldDef: TFieldDef; ABlobBuf: PBufBlobField; cursor: TSQLCursor; ATransaction: TSQLTransaction);
var
ODBCCursor: TODBCCursor;
Res: SQLRETURN;
StrLenOrInd:SQLLEN;
BlobBuffer:pointer;
BlobBufferSize,BytesRead:SQLINTEGER;
BlobMemoryStream:TMemoryStream;
begin
ODBCCursor:=cursor as TODBCCursor;
// Try to discover BLOB data length
// NB MS ODBC requires that TargetValuePtr is not nil, so we supply it with a valid pointer, even though BufferLength is 0
StrLenOrInd:=0;
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_BINARY, @BlobBuffer, 0, @StrLenOrInd);
if Res<>SQL_NO_DATA then
ODBCCheckResult(Res, SQL_HANDLE_STMT, ODBCCursor.FSTMTHandle, 'Could not get field data for field "%s" (index %d).',[FieldDef.Name, FieldDef.Index+1]);
// Read the data if not NULL
if StrLenOrInd<>SQL_NULL_DATA then
begin
// Determine size of buffer to use
if StrLenOrInd<>SQL_NO_TOTAL then begin
// Size is known on beforehand
// set size & alloc buffer
//WriteLn('Loading blob of length ',StrLenOrInd);
BlobBufferSize:=StrLenOrInd;
ABlobBuf^.BlobBuffer^.Size:=BlobBufferSize;
ReAllocMem(ABlobBuf^.BlobBuffer^.Buffer, BlobBufferSize);
// get blob data
if BlobBufferSize>0 then begin
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_BINARY, ABlobBuf^.BlobBuffer^.Buffer, BlobBufferSize, @StrLenOrInd);
ODBCCheckResult(Res, SQL_HANDLE_STMT, ODBCCursor.FSTMTHandle, 'Could not load blob data for field "%s" (index %d).',[FieldDef.Name, FieldDef.Index+1]);
end;
end else begin
// Size is not known on beforehand; read data in chuncks; write to a TMemoryStream (which implements O(n) writing)
BlobBufferSize:=DEFAULT_BLOB_BUFFER_SIZE;
// init BlobBuffer and BlobMemoryStream to nil pointers
BlobBuffer:=nil; // the buffer that will hold the chuncks of data; not to be confused with ABlobBuf^.BlobBuffer
BlobMemoryStream:=nil;
try
// Allocate the buffer and memorystream
BlobBuffer:=GetMem(BlobBufferSize);
BlobMemoryStream:=TMemoryStream.Create;
// Retrieve data in parts
repeat
Res:=SQLGetData(ODBCCursor.FSTMTHandle, FieldDef.Index+1, SQL_C_BINARY, BlobBuffer, BlobBufferSize, @StrLenOrInd);
ODBCCheckResult(Res, SQL_HANDLE_STMT, ODBCCursor.FSTMTHandle, 'Could not load (partial) blob data for field "%s" (index %d).',[FieldDef.Name, FieldDef.Index+1]);
// Append data in buffer to memorystream
if (StrLenOrInd=SQL_NO_TOTAL) or (StrLenOrInd>BlobBufferSize) then
BytesRead:=BlobBufferSize
else
BytesRead:=StrLenOrInd;
BlobMemoryStream.Write(BlobBuffer^, BytesRead);
until Res=SQL_SUCCESS;
// Copy memory stream data to ABlobBuf^.BlobBuffer
BlobBufferSize:=BlobMemoryStream.Size; // actual blob size
// alloc ABlobBuf^.BlobBuffer
ABlobBuf^.BlobBuffer^.Size:=BlobBufferSize;
ReAllocMem(ABlobBuf^.BlobBuffer^.Buffer, BlobBufferSize);
// read memory stream data into ABlobBuf^.BlobBuffer
BlobMemoryStream.Position:=0;
BlobMemoryStream.Read(ABlobBuf^.BlobBuffer^.Buffer^, BlobBufferSize);
finally
// free buffer and memory stream
BlobMemoryStream.Free;
if BlobBuffer<>nil then
Freemem(BlobBuffer,BlobBufferSize);
end;
end;
end;
end;
procedure TODBCConnection.FreeFldBuffers(cursor: TSQLCursor);
var
ODBCCursor:TODBCCursor;
begin
ODBCCursor:=cursor as TODBCCursor;
if ODBCCursor.FSTMTHandle <> SQL_NULL_HSTMT then
ODBCCheckResult(
SQLFreeStmt(ODBCCursor.FSTMTHandle, SQL_CLOSE),
SQL_HANDLE_STMT, ODBCCursor.FSTMTHandle, 'Could not close ODBC statement cursor.'
);
end;
procedure TODBCConnection.UpdateIndexDefs(IndexDefs: TIndexDefs; TableName: string); procedure TODBCConnection.UpdateIndexDefs(IndexDefs: TIndexDefs; TableName: string);
var var
Len: integer; Len: integer;

2
packages/fcl-db/tests/testsqldb.pas
View File

@ -566,8 +566,6 @@ var datatype: string;
begin begin
with SQLDBConnector do with SQLDBConnector do
begin begin
if not (sqLastInsertID in Connection.ConnOptions) then
Ignore(STestNotApplicable);
case SQLServerType of case SQLServerType of
ssMySQL: ssMySQL:
datatype := 'integer auto_increment'; datatype := 'integer auto_increment';