docs/api/sql/Predicates/ST_Relate.md

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# ST_Relate

Introduction: The first variant of the function computes and returns the [Dimensionally Extended 9-Intersection Model (DE-9IM)](https://en.wikipedia.org/wiki/DE-9IM) matrix string representing the spatial relationship between the two input geometry objects.

The second variant of the function evaluates whether the two input geometries satisfy a specific spatial relationship defined by the provided `intersectionMatrix` pattern.

![ST_Relate with intersectionMatrix pattern returning true](../../../image/ST_Relate/ST_Relate_true.svg "ST_Relate with intersectionMatrix pattern returning true")
![ST_Relate with intersectionMatrix pattern returning false](../../../image/ST_Relate/ST_Relate_false.svg "ST_Relate with intersectionMatrix pattern returning false")

!!!Note
    It is important to note that this function is not optimized for use in spatial join operations. Certain DE-9IM relationships can hold true for geometries that do not intersect or are disjoint. As a result, it is recommended to utilize other dedicated spatial functions specifically optimized for spatial join processing.

Format:

`ST_Relate(geom1: Geometry, geom2: Geometry)`

`ST_Relate(geom1: Geometry, geom2: Geometry, intersectionMatrix: String)`

Return type: `String`

Since: `v1.6.1`

SQL Example

```sql
SELECT ST_Relate(
        ST_GeomFromWKT('LINESTRING (1 1, 5 5)'),
        ST_GeomFromWKT('POLYGON ((3 3, 3 7, 7 7, 7 3, 3 3))')
)
```

Output:

```
1010F0212
```

SQL Example

```sql
SELECT ST_Relate(
        ST_GeomFromWKT('LINESTRING (1 1, 5 5)'),
        ST_GeomFromWKT('POLYGON ((3 3, 3 7, 7 7, 7 3, 3 3))'),
       "1010F0212"
)
```

Output:

```
true
```