- Supports is not distinct from
- Not for row-values
The not standardized binary is operator works in some SQL dialects like a null-safe comparison: It is similar to = but never returns unknown. Instead it returns false if only one argument is null or true if both arguments are null.
SELECT …
  FROM …
 WHERE c1 is c2Note that this is not the same as the standardized unary is [not] null operator as it allows two arbitrary expressions to be compared.
Related
- Standardised version of this operator: - IS NOT DISTINCT FROM(null-safe equals comparison)
- Tutorials: 
Normative References
<=> is not defined in the SQL standard.

