# ||

## Syntax

```sql
OR, ||
```

## Description

Logical `OR`. When both operands are non-`NULL`, the result is `1` if any operand is non-zero, and `0` otherwise. With a `NULL` operand, the result is `1` if the other operand is non-zero, and `NULL` otherwise. If both operands are `NULL`, the result is `NULL`.

For this operator, [short-circuit evaluation](https://mariadb.com/docs/server/reference/sql-structure/operator-precedence#short-circuit-evaluation) can be used.

{% hint style="warning" %}
Note that, if the `PIPES_AS_CONCAT` [SQL\_MODE](https://mariadb.com/docs/server/server-management/variables-and-modes/sql_mode) is set, `||` is used as a string concatenation operator. This means that `a || b` is the same as `CONCAT(a,b)`. See [CONCAT()](https://mariadb.com/docs/server/reference/sql-functions/string-functions/concat) for details.
{% endhint %}

### Oracle Mode

In [Oracle mode](https://app.gitbook.com/s/aEnK0ZXmUbJzqQrTjFyb/community-server/about/compatibility-and-differences/sql_modeoracle), `||` ignores [null](https://mariadb.com/docs/server/reference/data-types/null-values).

## Examples

```sql
SELECT 1 || 1;
+--------+
| 1 || 1 |
+--------+
|      1 |
+--------+

SELECT 1 || 0;
+--------+
| 1 || 0 |
+--------+
|      1 |
+--------+

SELECT 0 || 0;
+--------+
| 0 || 0 |
+--------+
|      0 |
+--------+

SELECT 0 || NULL;
+-----------+
| 0 || NULL |
+-----------+
|      NULL |
+-----------+

SELECT 1 || NULL;
+-----------+
| 1 || NULL |
+-----------+
|         1 |
+-----------+
```

In [Oracle mode](https://app.gitbook.com/s/aEnK0ZXmUbJzqQrTjFyb/community-server/about/compatibility-and-differences/sql_modeoracle):

```sql
SELECT 0 || NULL;
+-----------+
| 0 || NULL |
+-----------+
| 0         |
+-----------+
```

## See Also

## See Also

* [Operator Precedence](https://mariadb.com/docs/server/reference/sql-structure/operators/operator-precedence)
* [Oracle mode](https://app.gitbook.com/s/aEnK0ZXmUbJzqQrTjFyb/community-server/about/compatibility-and-differences/sql_modeoracle)

<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)

{% @marketo/form formId="4316" %}