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→Checking for NULL Values
=== Checking for NULL Values ===
In addition to being able to check for the value of a column, it isw also possible to check for columns that contain no value. Columns that have no value are said to contain NULL values. Not surprisingly, therefore, we can check for an empty column by looking for equality with NULL(although pay careful attention to the fact that we must now us 'IS' in place of the '=':
<pre>
SELECT * FROM products WHERE prod_name = IS NULL
</pre>
