On 3 February 2018 at 12:04, Tom Lane <t...@sss.pgh.pa.us> wrote: > Perhaps more useful to discuss: would that truly be the semantics we want, > or should we just evaluate the expression and have done? It's certainly > arguable that "IN (random())" ought to draw an error, not compute some > random value and use that. But if you are insistent on partition bounds > being immutable in any strong sense, you've already got problems, because > e.g. a timestamptz literal's interpretation isn't necessarily fixed. > It's only after we've reduced the original input to Datum form that we > can make any real promises about the value not moving. So I'm not seeing > where is the bright line between "IN ('today')" and "IN (random())".
I see there's been some progress on this thread that's probably gone a bit beyond here without the discussion about the desired semantics. To kick that off, I'm wondering, in regards to the comment about 'today' vs random(); how does this differ from something like: CREATE VIEW ... AS SELECT ... FROM ... WHERE datecol = 'today'; ? In this case 'today' is going to be evaluated during the parse analysis that's done during CREATE VIEW. Why would partitioning need to be treated differently? -- David Rowley http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services