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MySQL NDB Cluster API Developer Guide
Download this Manual NdbTransaction::writeTuple()

Description.  This method is used with NdbRecord to write a tuple of data.


const NdbOperation* writeTuple
      const NdbRecord* key_rec,
      const char* key_row,
      const NdbRecord* attr_rec,
      const char* attr_row,
      const unsigned char* mask = 0,
      const NdbOperation::OperationOptions* opts = 0,
      Uint32 sizeOfOptions = 0

Parameters.  This method takes the following parameters:

  • key_rec is a pointer to an NdbRecord for either a table or an index. If on a table, then the operation uses a primary key; if on an index, then the operation uses a unique key. In either case, the key_rec must include all columns of the key.

  • The key_row passed to this method defines the primary or unique key of the tuple to be written, and must remain valid until execute() is called.

  • attr_rec is an NdbRecord referencing the attribute to be written.


    For unique index operations, the attr_rec must refer to the underlying table of the index, not to the index itself.

  • attr_row is a buffer containing the new data.

  • The mask, if not NULL, defines a subset of attributes to be written. The mask is copied, and so does not need to remain valid after the call to this method returns.

  • OperationOptions (opts) can be used to provide more finely-grained control of operation definitions. An OperationOptions structure is passed with flags indicating which operation definition options are present. Not all operation types support all operation options; for the options supported by each type of operation, see Section, “NdbTransaction::readTuple()”.

  • The optional sizeOfOptions parameter is used to provide backward compatibility of this interface with previous definitions of the OperationOptions structure. If an unusual size is detected by the interface implementation, it can use this to determine how to interpret the passed OperationOptions structure. To enable this functionality, the caller should pass sizeof(NdbOperation::OperationOptions) for the value of this argument.

Return value.  A const pointer to the NdbOperation representing this write operation. The operation can be checked for errors if and as necessary.