On 5/3/17 02:56, Pavel Stehule wrote:
> Sometimes I have to solve the result types of some query. It is
> invisible in psql. You have to materialize table or you have to
> create view. Now, when we can enhance \g command, we can introduce
> query describing
>
> some like
>
> select a, b from foo
> \gdesc
>
> | type | length | collation | ....
> ------------------------------------------------
> a | varchar | 30 |
> b | numeric | 20 |
>
>
> here is the patch. It is based on PQdescribePrepared result.
I have often wished for functionality like this, so I'm in favor of
investigating this.
I don't think you need a separate call to prepare the query. You can
get the result column types using PQftype(). (Hmm, you can get the
typmod that way, but not the collation.)
My thinking in the past has been to put the column types either in the
column headers, like "colname (coltype)", or in the footer, along with
the actual query result.
--
Peter Eisentraut http://www.2ndQuadrant.com/
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