docs/api/sql/geography/Geography-Functions/ST_DWithin.md

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# ST_DWithin

Introduction: Tests whether two geographies are within a given geodesic distance (in meters) of each other on the sphere. The minimum great-circle distance between any two points on the two geographies is compared against the threshold; the test is inclusive (returns true when the minimum distance equals the threshold).

![ST_DWithin returning true](../../../../image/ST_DWithin_geography/ST_DWithin_geography_true.svg "ST_DWithin returning true")
![ST_DWithin returning false](../../../../image/ST_DWithin_geography/ST_DWithin_geography_false.svg "ST_DWithin returning false")

Format:

`ST_DWithin (A: Geography, B: Geography, distance: Double)`

Return type: `Boolean`

Since: `v1.9.1`

SQL Example

```sql
SELECT ST_DWithin(
  ST_GeogFromWKT('POINT (0 0)', 4326),
  ST_GeogFromWKT('POINT (0 1)', 4326),
  200000.0
);
```

Output:

```
true
```

The same pair of points with a tighter threshold:

```sql
SELECT ST_DWithin(
  ST_GeogFromWKT('POINT (0 0)', 4326),
  ST_GeogFromWKT('POINT (0 1)', 4326),
  100000.0
);
```

Output:

```
false
```