Re: Query to retrieve the index columns when a function is used.

David Rowley <dgrowleyml@gmail.com> writes:
> On Tue, 10 Mar 2020 at 02:16, Sterpu Victor <victor@caido.ro> wrote:
>> How can I retrieve this detail?

> Those details are in the indexprs column.  There's an item there for
> each 0 valued indkey. It's not going to be particularly easy for you
> to parse that from SQL.  Internally in PostgreSQL, we have functions
> that could give you that information easily, but to access those from
> SQL you'd need to write something in C.

You could use pg_get_indexdef().  I agree that parsing indexprs from
SQL is not to be recommended --- aside from being very complex, it
would break on a regular basis, because we change those structs often.

            regards, tom lane