DB2 graphic  QMF Version 8

NULL

If a table is created and only partially filled with data, the locations in which nothing is entered contain a code word called NULL, meaning value unknown. NULL is not the same as any of these values:

Each of these values can be entered in a row and column of some table. NULL occurs where no value was entered, or where the value was specifically set to NULL. It prints and displays as a single hyphen (-).

The VALUE scalar function can be used to change how a null is printed and displayed. See String functions.

To select rows that have NULL in a column, enter:

WHERE columnname IS NULL

Examples:


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Copyright IBM Corporation 1982,2004 Copyright IBM Corporation 1982, 2004
timestamp Last updated: March, 2004