PostgreSQL performance citext

Question

I'm trying to determine the performance characteristics of citext. In Microsoft SQL Server, the nvarchar(max) has performance hits when there is excessive memory grants required to use it versus something like a varchar(50). There are other performance hits that come in to play also. I'm trying to determine if citext in PostgreSQL has similar issues. We have a PostgreSQL backed web-app that is horribly slow and I'm wondering if the extensive use of the citext data type is contributing. Any thoughts on this? Thank you!

Answer 1

Case insensitive comparison is always costly than case sensitive one. The documentation also cites that in Limitations section. As I understood, the main problem is that you have a performance issue and you cannot locate the culprit(s). I suggest you to use pgBadger or pg_stat_statements to detect slow queries.