IS NOT DISTINCT FROM (null-safe equals comparison)

BigQueryDb2 (LUW)H2MariaDBMySQLOracle DBPostgreSQLSQL ServerSQLite20082010201220142016201820202022✓ 3.39.0 - 3.43.0b⊘ 3.15.0 - 3.38.0b⊘ 3.5.7 - 3.14.2⚠ 2022c⊘ 2008R2 - 2019✓ 8.3 - 16⊘ 11gR1 - 21c⊘ 5.0 - 8.0.34a⊘ 5.1 - 10.11a✓ 1.4.192 - 2.2.220⚠ 11.5.0 - 11.5.8c⊘ 9.7 - 11.1⚠ 2.0c⊘ 2.0
  1. Supports the non-standard spaceship operator instead: <=>
  2. Supports the non-standard binary is operator instead
  3. Not for row-values

The equals comparison (=) returns unknown if one of the compared values is the null value. Is not distinct from 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 …

Normative References

Is not distinct from is defined in ISO/IEC 9075-2:2023 as the optional feature T152, “DISTINCT predicate with negation”.

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