TParam.GetDataSize Method

Returns the number of bytes needed to hold the parameter's value in the format used by the corresponding type of database field.

Pascal

function GetDataSize: Integer;

C++

__fastcall int GetDataSize();

Description

Call GetDataSize to determine the number of bytes used to represent the parameter's value. GetDataSize indicates the buffer size needed before calling the GetData method. The value returned by GetDataSize depends on the Value of the parameter. For some values of DataType, this is always the same:

DataType	Value of DataSize
ftBoolean	2
ftSmallint	2
ftWord	2
ftAutoInc	4
ftDate	4
ftInteger	4
ftTime	4
ftCurrency	8
ftDateTime	8
ftFloat	8
ftTimeStamp	16
ftBCD	34
ftString	length of the string + 1
ftFixedChar	length of the string + 1
ftVarBytes	If the value is a Variant array, the number of elements in the array, else 0
ftBytes	If the value is a Variant array, the number of elements in the array, else 0
ftBlob	number of bytes of blob data
ftFmtMemo	number of bytes of blob data
ftGraphic	number of bytes of blob data
ftMemo	length of memo string + 1
ftDBaseOle	number of bytes of blob data
ftParadoxOle	number of bytes of blob data
ftOraBlob	number of bytes of blob data
ftOraClob	number of bytes of blob data
ftTypedBinary	number of bytes of data
ftADT	0
ftArray	0
ftDataSet	0
ftReference	0
ftCursor	0
ftUnknown	raises an EDatabaseError exception

Note: The size returned by GetDataSize is the size required for the physical database representation of the Value. The field object that corresponds to that physical database field may store its data in another format requiring a different number of bytes.