O Michael Glaesemann έγραψε στις Jun 3, 2005 :
> > On Jun 3, 2005, at 9:23 PM, Markus Bertheau β? wrote: > > > This also bypasses the built in postgresql boolean literal parsing. > > > > I think casting from text to boolean should be possible, and use the > > same algorithm that's used when casting from "unknown" to boolean. > > Actually, looking at the system tables, I don't think it is. There > don't appear to be any casts to (or from) boolean. I may be looking > at it wrong, but that's how it appears to me. Corrections, anyone? > > select type_source.typname as source, type_target.typname as target > from pg_cast > join pg_type type_source on (castsource = type_source.oid) > join pg_type type_target on (casttarget = type_target.oid) > where type_target.typname = 'bool' > or type_source.typname = 'bool' > order by type_source.typname; > > source | target > --------+-------- > (0 rows) > > This is in v8.0.3 Also according to the docs: http://www.postgresql.org/docs/current/static/datatype-boolean.html "Tip: Values of the boolean type cannot be cast directly to other types (e.g., CAST (boolval AS integer) does not work). This can be accomplished using the CASE expression: CASE WHEN boolval THEN 'value if true' ELSE 'value if false' END." I suppose the reverse must be true also. > > Michael Glaesemann > grzm myrealbox com > > PS. Please don't top post. > > > ---------------------------(end of broadcast)--------------------------- > TIP 2: you can get off all lists at once with the unregister command > (send "unregister YourEmailAddressHere" to [EMAIL PROTECTED]) > -- -Achilleus ---------------------------(end of broadcast)--------------------------- TIP 7: don't forget to increase your free space map settings
