COLUMN_CHECK

Verify dynamic column integrity. This function checks if a blob containing dynamic columns is valid and returns 1 if it is, 0 otherwise.

Syntax

COLUMN_CHECK(dyncol_blob);

Description

Check if dyncol_blob is a valid packed dynamic columns blob. Return value of 1 means the blob is valid, return value of 0 means it is not.

Rationale: Normally, one works with valid dynamic column blobs. Functions like COLUMN_CREATE, COLUMN_ADD, COLUMN_DELETE always return valid dynamic column blobs. However, if a dynamic column blob is accidentally truncated, or transcoded from one character set to another, it will be corrupted. This function can be used to check if a value in a blob field is a valid dynamic column blob.

_{This page is licensed: CC BY-SA / Gnu FDL}