QAD BI v3 – Tech Level 2 Certification - Part 1 > SQL – Preview > Dealing with NULL values
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Dealing with NULL values
 
The result can be TRUE, indicating there is a match. The result can be FALSE, indicating there is not a match. The result can also be UNKNOWN, if either of the values being matched on have a null (blank) value. The result is UNKNOWN even if both values are null.
Dealing with NULL values – continued
 
NOTE: NULL <> NULL cannot use NULL value to compare