Waiting for 9.6 – Add a \gexec command to psql for evaluation of computed queries.

On 4th of April, Tom Lane committed patch:

Add a \gexec command to psql for evaluation of computed queries.
\gexec executes the just-entered query, like \g, but instead of printing
the results it takes each field as a SQL command to send to the server.
Computing a series of queries to be executed is a fairly common thing,
but up to now you always had to resort to kluges like writing the queries
to a file and then inputting the file.  Now it can be done with no
intermediate step.
The implementation is fairly straightforward except for its interaction
with FETCH_COUNT.  ExecQueryUsingCursor isn't capable of being called
recursively, and even if it were, its need to create a transaction
block interferes unpleasantly with the desired behavior of \gexec after
a failure of a generated query (i.e., that it can continue).  Therefore,
disable use of ExecQueryUsingCursor when doing the master \gexec query.
We can still apply it to individual generated queries, however, and there
might be some value in doing so.
While testing this feature's interaction with single-step mode, I (tgl) was
led to conclude that SendQuery needs to recognize SIGINT (cancel_pressed)
as a negative response to the single-step prompt.  Perhaps that's a
back-patchable bug fix, but for now I just included it here.
Corey Huinker, reviewed by Jim Nasby, Daniel Vérité, and myself

Continue reading Waiting for 9.6 – Add a \gexec command to psql for evaluation of computed queries.

Waiting for 8.5 – DO

On 22nd of September, Tom Lane committed a patch by Petr Jelinek:

Log Message:
Implement the DO statement TO support execution OF PL code WITHOUT HAVING
PROCEDURAL languages now have an additional entry point, namely a FUNCTION
TO EXECUTE an inline code block.  This seemed a better design than trying
TO hide the transient-ness OF the code FROM the PL.  AS OF this patch, ONLY
plpgsql has an inline handler, but probably people will soon WRITE handlers
FOR the other standard PLs.
IN passing, remove the long-dead LANCOMPILER OPTION OF CREATE LANGUAGE.
Petr Jelinek

Continue reading Waiting for 8.5 – DO