=================
Statement options
=================

Statement options are a comma-separated list of directives that influence how a statement is planned or executed. They are supplied through an ``OPTIONS`` clause.

Syntax
######

.. raw:: html
    :file: statement_options.diagram.svg

Scope
#####

An ``OPTIONS`` clause is **statement-level**: it applies to the statement as a whole, not to an individual clause within it. It is written once, at the end of a top-level statement — a ``SELECT``, ``INSERT``, ``UPDATE``, ``DELETE``, or ``EXECUTE CONTINUATION``. It cannot be attached to a nested query such as a subquery, a common table expression, or an index definition; placing ``OPTIONS`` anywhere other than at the end of a top-level statement is a syntax error.

An option affects only the statement it is attached to. It does not change any connection-wide or transaction-wide setting, and it is not remembered for later statements — each statement that needs an option must specify it.

Which options are valid depends on the statement: some apply only to read-only ``SELECT`` queries, others only to data-modifying statements. See each option's page for details.

.. toctree::
    :maxdepth: 1

    statement_options/ISOLATION_LEVEL_SNAPSHOT