> 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

{% 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 %}