is [not] true|false|unknown

BigQueryDb2 (LUW)MariaDBMySQLOracle DBPostgreSQLSQL ServerSQLite200520072009201120132015201720192021⚠ 3.5.7 - 3.40.0a⊘ 2008R2 - 2022✓ 8.3+⊘ 11gR1 - 21c✓ 5.0+✓ 5.1+⚠ 11.5.0 - 11.5.7a⊘ 9.7 - 11.1✓ 2.0+a⚠ 2.0a
  1. No is [not] unknown. Use is [not] null instead