Null
Warning: You are browsing the documentation for Symfony 2.x, which is no longer maintained.
Read the updated version of this page for Symfony 7.3 (the current stable version).
Caution
The Null constraint is deprecated since Symfony 2.7
and will be removed in Symfony 3.0. Use the
IsNull constraint instead.
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Creative Commons BY-SA 3.0 license.