Categories:: Geospatial functions

ST_COVEREDBY¶

Returns TRUE if no point in one geospatial object is outside another geospatial object. In other words:

GEOGRAPHY object g1 is outside GEOGRAPHY object g2.
GEOMETRY object g1 is outside GEOMETRY object g2.

This is equivalent to ST_COVERS(g2, g1).

Although ST_COVEREDBY and ST_WITHIN might seem similar, the two functions have subtle differences. For details on the differences between “covered by” and “within”, see the Dimensionally Extended 9-Intersection Model (DE-9IM).

Note

This function does not support using a GeometryCollection or FeatureCollection as input values.

Tip

You can use the search optimization service to improve the performance of queries that call this function. For details, see Search Optimization Service.

See also:: ST_COVERS , ST_WITHIN

Syntax¶

ST_COVEREDBY( <geography_expression_1> , <geography_expression_2> )

ST_COVEREDBY( <geometry_expression_1> , <geometry_expression_2> )

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Arguments¶

geography_expression_1: A GEOGRAPHY object that is not a GeometryCollection or FeatureCollection.
geography_expression_2: A GEOGRAPHY object that is not a GeometryCollection or FeatureCollection.
geometry_expression_1: A GEOMETRY object that is not a GeometryCollection or FeatureCollection.
geometry_expression_2: A GEOMETRY object that is not a GeometryCollection or FeatureCollection.

Returns¶

BOOLEAN.

Usage notes¶

For GEOMETRY objects, the function reports an error if the two input GEOMETRY objects have different SRIDs.

Examples¶

GEOGRAPHY examples¶

This shows a simple use of the ST_COVEREDBY function:

create table geospatial_table_01 (g1 GEOGRAPHY, g2 GEOGRAPHY);
insert into geospatial_table_01 (g1, g2) values 
    ('POLYGON((0 0, 3 0, 3 3, 0 3, 0 0))', 'POLYGON((1 1, 2 1, 2 2, 1 2, 1 1))');

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SELECT ST_COVEREDBY(g1, g2) 
    FROM geospatial_table_01;
+----------------------+
| ST_COVEREDBY(G1, G2) |
|----------------------|
| False                |
+----------------------+

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