T301, “Functional dependencies”

BigQueryDb2 (LUW)DerbyH2MariaDBMySQLOracle DBPostgreSQLSQL ServerSQLite2005200720092011201320152017201920212023⚡ 3.5.7 - 3.50.0⊘ 2008R2 - 2022⚠ 9.1 - 18⊘ 8.3 - 9.0⊘ 11gR1 - 23.9✓ 5.7 - 9.4.0⚡ 5.0 - 5.6⚡ 5.1 - 12.0.2⚡ 1.4.192 - 2.4.240⊘ 10.16.1.1 - 10.17.1.0⊘ 9.7 - 12.1.2⊘ 2.0

The underpinning tests for this page don’t cover all known functional dependencies of the SQL standard yet. Just those listed below.

BigQuery 2025-09-02Db2 (LUW) 12.1.2Derby 10.17.1.0H2 2.4.240⚡a⚡a⚡a⚡a⚡aMariaDB 12.0.2⚡a⚡a⚡a⚡a⚡aMySQL 9.4.0Oracle DB 23.9PostgreSQL 18bSQL Server 2022SQLite 3.50.0⚡a⚡a⚡a⚡a⚡aBase table PRIMARY KEYBase table UNIQUEJoined tablesWHERE clauseGROUP BY clause
  1. ⚡Doesn’t fail if there is no functional dependency (per default)
  2. Not following joins to PRIMARY KEYs or UNIQUE constraints
Optional Features

Normative References

The known functional dependencies of SQL are specified in ISO/IEC 9075-2:2023 §4.26. The respective optional feature T301, “Functional dependencies” first appeared in the edition of 1999.

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