Michael Glaesemann <grzm@xxxxxxxxxxxxxxx> writes: > test=# select '2008-02-15' > CURRENT_DATE; > Here, we're comparing against a date type, so Postgres treats > '2008-02-15' as a date. It might be worth pointing out that this is not magic, but an application of the general rule mentioned at step 2a here: http://www.postgresql.org/docs/8.3/static/typeconv-oper.html In any case where Postgres is trying to interpret a binary operator, and one input has a known type while the other is an unknown-type literal constant, the preferred interpretation will be that the constant has the same type as the known-type input. In a case like 'today is ' || '2008-02-16', *both* inputs are initially unknown-type literals. There is a fallback heuristic that prefers to resolve such cases as type text, which is why you get text concatenation rather than a "couldn't resolve operator" error. In no case does Postgres look at the content of an unknown literal to determine its type. '2008-02-16' is not treated differently from 'foobar'. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org/
