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saLongOrLobReader_t fnReader , size_t
nReaderWantedPieceSize , void *pAddlData );
Starts reading of Long or BLob(CLob) value using user defined callback.
fnReader. The name of user function used for Long or BLob(CLob) data reading. The function must have syntax declared by saLongOrLobReader_t typedef .
nReaderWantedPieceSize. Size of piece of data user want to get to callback function.
pAddData. Additional data, passed to callback function.
When you call SACommand::FetchNext method (after a command execution) all fields are updated by their values, including Long and BLob(CLob) fields. If you want to control piecewise reading of Long or BLob(CLob) data you should do the following:
ReadLongOrLob method will repeatedly call user defined function:
void <function Name>(SAPieceType_t ePieceType,
User defined function has the following parameters:
ePieceType. Parameter passed to the function from SQLAPI++ Library mechanisms. It defines which piece of data value was read. Can be one of the next SAPieceType_t enum values:
pBuf. Pointer to the buffer that contains the data block read from database.
nLen. The actual size of data in buffer pBuf.
nBlobSize. Maximum size of whole Long or BLob(CLob) field (if DBMS server allows to know it before whole field was read; otherwise 0).
pAddData. An additional data user want to pass to the function.
To get more information about reading Long and BLob(CLob) data see Query examples - Step 6.
Server specific notes
No specific information.
Problems and Questions
If you haven't found the answer to your questions or have some problems on using the Library, please, send e-mail to firstname.lastname@example.org.