SQL Dialects Reference/Functions and expressions/Misc expressions

Misc functions edit

This page includes comparison tables which can be big and complex.

While it's perfectly all right to view them in their complete state, it is recommended to install a comparison tables extension that would allow to select particular columns of interest for comparison.

SQL version Feature Standard
SQL:2011
DB2 Firebird Ingres Linter MSSQL MySQL
Vers. 5.x
MonetDB Oracle
Vers. 11.x
PostgreSQL SQLite Virtuoso
? Convert value val to data type type CAST(val AS type) ? CAST(val AS type) ? CAST(val AS type)
CASTexpression as type
TO_CHAR
TO_NUMBER
TO_DATE
CAST(val AS type)
CONVERT(type, val, style)
CONVERT(val, type)
CAST(val AS type)
CAST(val AS type)
CONVERT(val, type)
CAST(val AS type) CAST(val AS type)
val::type
CAST(val AS type) ?
? Replace NULL within a val with a fallback value, return val intact, if it's non-NULL COALESCE(val, fallback) ? ? ? NVL(val, fallback) COALESCE(val, fallback)
ISNULL(val, fallback)
IFNULL(val, fallback) COALESCE(val, fallback) COALESCE(val, fallback)
NVL(val, fallback)
COALESCE(val, fallback) IFNULL(val, fallback)
COALESCE(val, fallback)
?
? Return the first non-NULL value from a list of values (val1, val2, ...) COALESCE(val1, val2, ...) COALESCE(val1, val2) COALESCE(val1, val2, ...) ? COALESCE(val1, val2, ...) COALESCE(val1, val2, ...) COALESCE(val1, val2, ...) COALESCE(val1, val2, ...) COALESCE(val1, val2, ...) COALESCE(val1, val2, ...) COALESCE(val1, val2, ...) ?
? Convert particular values to NULL: return NULL if a = b otherwise keep a NULLIF(a, b) ? NULLIF(a, b) ? NULLIF(a, b) NULLIF(a, b) NULLIF(a, b) NULLIF(a, b) NULLIF(a, b) NULLIF(a, b) NULLIF(a, b) ?