2017-04-06 8:08 GMT+02:00 Pavel Stehule <pavel.steh...@gmail.com>: > > > 2017-04-05 23:22 GMT+02:00 Tom Lane <t...@sss.pgh.pa.us>: > >> Andres Freund <and...@anarazel.de> writes: >> > I'd like some input from other committers whether we want this. I'm >> > somewhat doubtful, but don't have particularly strong feelings. >> >> I don't really want to expose the workings of the plancache at user level. >> The heuristics it uses certainly need work, but it'll get hard to change >> those once there are SQL features depending on it. >> > > I am very sceptical about enhancing heuristics - but I am open to any > proposals. > > The advanced users disable a plan cache with dynamic SQL. But this > workaround has strong disadvantages: > > 1. it is vulnerable to SQL injection > 2. it is less readable > > > >> >> Also, as you note, there are debatable design decisions in this particular >> patch. There are already a couple of ways in which control knobs can be >> attached to plgsql functions (i.e. custom GUCs and the comp_option stuff), >> so why is this patch wanting to invent yet another fundamental mechanism? >> And I'm not very happy about it imposing a new reserved keyword, either. >> > > 1. > > custom GUC has not local scope - so it doesn't allow precious settings. > With PRAGMA I have perfect control what will be impacted. > > #option has function scope > > 2. I'll not introduce a PRAGMA keyword just for this feature. We would to > implement autonomous transactions. There was not any objection against this > feature. The PRAGMA allows to share PL/SQL syntax and functionality. > > >> A bigger-picture question is why we'd only provide such functionality >> in plpgsql, and not for other uses of prepared plans. >> > > It is out of scope of this patch. >
The scope of this patch can be enhanced - but it is different task because user interface should be different. > > >> >> Lastly, it doesn't look to me like the test cases prove anything at all >> about whether the feature does what it's claimed to. >> > > I can enhance regress tests - currently there are not direct access to > these attributes - so the tests can be indirect only :( > > Regards > > Pavel > > >> >> regards, tom lane >> > >
