# SPATIAL INDEX

## Description

On [MyISAM](https://mariadb.com/docs/server/server-usage/storage-engines/myisam-storage-engine), [Aria](https://mariadb.com/docs/server/server-usage/storage-engines/aria) and [InnoDB](https://mariadb.com/docs/server/server-usage/storage-engines/innodb) tables, MariaDB can create spatial indexes (an R-tree index) using syntax similar to that for creating regular indexes, but extended with the `SPATIAL` keyword. Columns in spatial indexes must be declared `NOT NULL`.

Spatial indexes can be created when the table is created, or added after the fact:

```sql
CREATE TABLE geom (g GEOMETRY NOT NULL, SPATIAL INDEX(g));
```

```sql
ALTER TABLE geom ADD SPATIAL INDEX(g);
```

```sql
CREATE SPATIAL INDEX sp_index ON geom (g);
```

`SPATIAL INDEX` creates an `R-tree` index. For storage engines that support non-spatial indexing of spatial columns, the engine creates a `B-tree` index. A `B-tree` index on spatial values is useful for\
exact-value lookups, but not for range scans.

For more information on indexing spatial columns, see [CREATE INDEX](https://mariadb.com/docs/server/reference/sql-statements/data-definition/create/create-index).

To drop spatial indexes, use [ALTER TABLE](https://mariadb.com/docs/server/reference/sql-statements/data-definition/alter/alter-table) or [DROP INDEX](https://mariadb.com/docs/server/reference/sql-statements/data-definition/drop/drop-index):

```sql
ALTER TABLE geom DROP INDEX g;
```

```sql
DROP INDEX sp_index ON geom;
```

### Data-at-Rest Encryption

If [innodb\_checksum\_algorithm](https://mariadb.com/docs/server/clients-and-utilities/administrative-tools/innochecksum) is set to `full_crc32` or `strict_full_crc32`, and if the table does not use [ROW\_FORMAT=COMPRESSED](https://mariadb.com/docs/server/server-usage/storage-engines/innodb/innodb-row-formats), InnoDB spatial indexes are encrypted if the table is encrypted.

See [MDEV-12026](https://jira.mariadb.org/browse/MDEV-12026) for more information.

<sub>*This page is licensed: GPLv2, originally from*</sub> [<sub>*fill\_help\_tables.sql*</sub>](https://github.com/MariaDB/server/blob/main/scripts/fill_help_tables.sql)

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