You are currently viewing archive for 12 July 2007
Category: Study
Posted by: hajime osako

Column 'Key' has three value: PRI, UNI and MUL. Even this Key is null, still this column could be the part of index as a secondary column.

MUL indicates the first column of a non-unique index or a unique value index that can contain NULL.

Category: Web dev
Posted by: hajime osako