ST_SRID()¶

TL;DR¶

Use ST_SRID() to read the SRID metadata carried by a geometry value.

Returns the spatial reference identifier (SRID) of a geometry value.

Syntax¶

ST_SRID(geom)

Arguments¶

Argument	Description
`geom`	A `GEOMETRY` or `GEOMETRY32` value.

Return Value¶

Returns the SRID as UINT32.

Usage Notes¶

A geometry constructed without an SRID has SRID 0.
SRID is carried in the geometry expression or column type, rather than its WKB payload; it propagates through tested derived functions.

Examples¶

DROP DATABASE IF EXISTS geo_srid_demo;
CREATE DATABASE geo_srid_demo;
USE geo_srid_demo;

SELECT ST_SRID(ST_GeomFromText('POINT(1 2)', 4326)) AS srid;

DROP DATABASE geo_srid_demo;

See Also¶