On 11/25/2017 10:33 PM, Fabien COELHO wrote: > > This patch adds \if support to pgbench, similar to psql's version added > in March. > > This patch brings a consistent set of features especially when combined > with two other patches already in the (slow) CF process: > > - https://commitfest.postgresql.org/10/596/ .. /15/985/ > adds support for booleans expressions (comparisons, logical > operators, ...). This enhanced expression engine would be useful > to allow client-side expression in psql. > > - https://commitfest.postgresql.org/10/669/ .. /15/669/ > adds support for \gset, so that pgbench can interact with a database > and extract something into a variable, instead of discarding it. > > This patch adds a \if construct so that an expression on variables, > possibly with data coming from the database, can change the behavior of > a script.
I have given this patch a pretty good shake and I'm happy with it. I did not test it with the other two patches, only on its own. > A partial evaluation is performed to detect structural errors (eg > missing endif, else after else...) when the script is parsed, so that > such errors cannot occur when a script is running. Very good. > A new automaton state is added to quickly step over false branches. This one took me a little while to understand while reading the patch, but mostly because of how diff doesn't handle moving things around. > TAP tests ensure reasonable coverage of the feature. And the documentation seems sufficient, as well. It's a shame this feature uses \elif instead of \elsif to be closer to plpgsql, but I suppose this ship already sailed when psql chose \elif, and I think it is correct that this patch follows psql. Marking as ready for committer. -- Vik Fearing +33 6 46 75 15 36 http://2ndQuadrant.fr PostgreSQL : Expertise, Formation et Support
