Can I use… <=> (Spaceship operator)

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  1. Supports is not distinct from

The not standardized spaceship 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.

  FROM …
 WHERE c1 <=> c2

Note that this is not a three-way comparison in the way PHP or C++ use the spaceship operator.

Normative References

<=> is not defined in the SQL standard.

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