[ DE ]

ID133, "The implicit null ordering when null ordering is not specified"


BigQuery 2025年12月09日Db2 (LUW) 12.1.3DuckDB 1.4.0aaaaH2 2.4.240MariaDB 12.1.2MySQL 9.5.0Oracle DB 23.26.0PostgreSQL 18SQL Server 2025SQLite 3.51.0NULL is very small NULL is very big NULL comes first NULL comes last
  1. Configurable: set default_null_order = [NULLS_FIRST | NULLS_LAST | NULLS_FIRST_ON_ASC_LAST_ON_DESC | NULLS_LAST_ON_ASC_FIRST_ON_DESC]

Normative References

The implementation defined item ID133, "The implicit null ordering when null ordering is not specified" is defined in ISO/IEC 9075-2:2023. The standard edition of 1989 did explicitly defined the null ordering as "implementator defined" but also required null values to be treated either greater or smaller than non-null values. This remained standard until 2003, when nulls first | last was introduced. Since then, the <null ordering> is implementation defined and may depend on the presence of asc and desc but must not depend on context outside the order by clause.

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