How to restrict

PostgreSQL 10.x

What is the best way to restrict the values on a text field to make sure they only contain particular values: Example: The field “type” can only contain the values of “X”, “Y” and “Z”. Would a trigger be the best strategy? Or is there a special SQL type I should use in this particular case?

Thanks,

LANCE CAMPBELL<https://directory.illinois.edu/person/lance>
Software Architect

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