2.3.14 The Key_part_ptr Structure

Abstract

This section describes the Key_part_ptr structure.

Parent class.  Ndb

Description.  Key_part_ptr provides a convenient way to define key-part data when starting transactions and computing hash values, by passing in pointers to distribution key values. When the distribution key has multiple parts, they should be passed as an array, with the last part's pointer set equal to NULL. See Section 2.3.15.1.21, “Ndb::startTransaction()”, and Section 2.3.15.1.3, “Ndb::computeHash()”, for more information about how this structure is used.

Attributes.  A Key_part_ptr has the attributes shown in the following table:

AttributeTypeInitial ValueDescription
ptrconst void*nonePointer to one or more distribution key values
lenunsignednoneThe length of the pointer