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MySQL NDB Cluster API Developer Guide
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2.3.24.43 NdbInterpretedCode::read_attr()

Description.  The read_attr() method is used to read a table column value into a program register. The column may be specified either by using its attribute ID or as a pointer to a Column object.

Signature.  This method can be called in either of two ways. The first of these is by referencing the column by its attribute ID, as shown here:

int read_attr
    (
      Uint32 RegDest,
      Uint32 attrId
    )

Alternatively, you can reference the column as a Column object, as shown here:

int read_attr
    (
      Uint32 RegDest,
      const NdbDictionary::Column* column
    )

Parameters.  This method takes two parameters, as described here:

  • The register to which the column value is to be copied (RegDest).

  • Either of the following references to the table column whose value is to be copied:

    • The table column's attribute ID (attrId)

    • A pointer to a column—that is, a pointer to an Column object referencing the table column

Return value.  Returns 0 on success, and -1 on failure.