Can I use… IS NOT DISTINCT FROM (null-safe equals comparison)


Partial SQL Server support since 2022. Full SQLite support since 3.39.0. Partial BigQuery support since 2.0. Full H2 support since 1.4.200. Partial Db2 (LUW) support since 11.5.7. Full PostgreSQL support since 8.3.BigQueryDb2 (LUW)H2MariaDBMySQLOracle DBPostgreSQLSQL ServerSQLite200520072009201120132015201720192021✓ 3.39.0+b⊘ 3.15.0 - 3.38.0b⊘ 3.5.7 - 3.14.2⚠ 2022c⊘ 2008R2 - 2019✓ 8.3+⊘ 11gR1 - 21c⊘ 5.0 - 8.0.31a⊘ 5.1 - 10.10a✓ 1.4.200+⚠ 11.5.0 - 11.5.7c⊘ 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.

SELECT …
  FROM …
 WHERE c1 IS NOT DISTINCT FROM c2

Normative References

Is not distinct from is defined in ISO/IEC 9075-2:2016 as the optional feature T152, “DISTINCT predicate with negation”.

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