# DUAL

## Description

You can use `DUAL` instead of a table name in situations where no tables are referenced, such as the following [SELECT](/docs/server/reference/sql-statements/data-manipulation/selecting-data/select.md) statement:

```sql
SELECT 1 + 1 FROM DUAL;
+-------+
| 1 + 1 |
+-------+
|     2 |
+-------+
```

`DUAL` is purely for the convenience of people who require that all `SELECT` statements should have`FROM` and possibly other clauses. MariaDB ignores the clauses. MariaDB does not require `FROM DUAL` if no tables are referenced.

FROM DUAL could be used when you only SELECT computed values, but require a `WHERE` clause, perhaps to test that a script correctly handles empty resultsets:

```sql
SELECT 1 FROM DUAL WHERE FALSE;
Empty set (0.00 sec)
```

## See Also

* [SELECT](/docs/server/reference/sql-statements/data-manipulation/selecting-data/select.md)

<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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