> For the complete documentation index, see [llms.txt](https://mariadb.com/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://mariadb.com/docs/server/reference/sql-structure/operators/logical-operators.md).

# Logical Operators

Learn about logical operators in MariaDB Server SQL. This section details operators like AND, OR, and NOT used to combine or negate conditions, essential for complex filtering and data selection.

{% columns %}
{% column %}
{% content-ref url="/pages/7gPMXNHL1INvNDnWsjsz" %}
[&&](/docs/server/reference/sql-structure/operators/logical-operators/and.md)
{% endcontent-ref %}
{% endcolumn %}

{% column %}
Evaluate logical AND with AND or &&, returning 1 when all operands are non-zero and not NULL, 0 when any operand is 0, and NULL otherwise.
{% endcolumn %}
{% endcolumns %}

{% columns %}
{% column %}
{% content-ref url="/pages/IDPY3OWBtg0RSrG4oYHv" %}
[!](/docs/server/reference/sql-structure/operators/logical-operators/not.md)
{% endcontent-ref %}
{% endcolumn %}

{% column %}
Negate an operand with logical NOT or !, returning 1 for 0, 0 for non-zero values, and NULL for NULL, with precedence affected by the HIGH\_NOT\_PRECEDENCE SQL\_MODE.
{% endcolumn %}
{% endcolumns %}

{% columns %}
{% column %}
{% content-ref url="/pages/MzUPJvF7PoBmX3cP8hJL" %}
[||](/docs/server/reference/sql-structure/operators/logical-operators/or.md)
{% endcontent-ref %}
{% endcolumn %}

{% column %}
Evaluate logical OR with OR or ||, returning 1 when any operand is non-zero and handling NULL operands per SQL logic; || concatenates strings under PIPES\_AS\_CONCAT.
{% endcolumn %}
{% endcolumns %}

{% columns %}
{% column %}
{% content-ref url="/pages/wmLGmcQaunuQWUfTJz7M" %}
[XOR](/docs/server/reference/sql-structure/operators/logical-operators/xor.md)
{% endcontent-ref %}
{% endcolumn %}

{% column %}
Evaluate exclusive OR with XOR, returning NULL if either operand is NULL and otherwise 1 when an odd number of operands is non-zero.
{% endcolumn %}
{% endcolumns %}

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