Description. This method is used to perform a scan.
virtual int readTuples ( LockMode mode = LM_Read, Uint32 flags = 0, Uint32 parallel = 0, Uint32 batch = 0 )
Parameters. This method takes the four parameters listed here:
mode; this is a
Scans with exclusive locks. When scanning with an exclusive lock, extra care must be taken due to the fact that, if two threads perform this scan simultaneously over the same range, then there is a significant probability of causing a deadlock. The likelihood of a deadlock is increased if the scan is also ordered (that is, using
NdbScanOperation::close()method is also affected by this deadlock, since all outstanding requests are serviced before the scan is actually closed.
One or more
ScanFlagvalues. Multiple values are
The number of fragments to scan in
0to require that the maximum possible number be used.
batchparameter specifies how many records will be returned to the client from the server by the next
NdbScanOperation::nextResult(true)method call. Use
0to specify the maximum automatically.Note
This parameter was ignored prior to MySQL 5.1.12, and the maximum was used (see Bug #20252).
0 on success,