PostgreSQL 9.5
PostgreSQL 9.5
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citext

F.7. citext

The citext module provides a case-insensitive character string type, citext. Essentially, it internally calls lower when comparing values. Otherwise, it behaves almost exactly like text.

F.7.1. Rationale

The standard approach to doing case-insensitive matches in PostgreSQL has been to use the lower function when comparing values, for example

SELECT * FROM tab WHERE lower(col) = LOWER(?);

This works reasonably well, but has a number of drawbacks:

  • It makes your SQL statements verbose, and you always have to remember to use lower on both the column and the query value.

  • It won't