>>>>> "Tom" == Tom Lane <t...@sss.pgh.pa.us> writes:
Tom> * I'm almost thinking that changing to list_union is a bad idea, A fair point. Though it looks like list_union is used in only about 3 distinct places, and two of those are list_union(NIL, blah) to simply remove dups from a single list. The third place is the cartesian-product expansion of grouping sets, which uses list_union_int to remove duplicates - changing the order there will give slightly user-surprising but not actually incorrect results. Presumably list_concat_unique should be considered to guarantee that it preserves the relative order of the two lists and of the non-duplicate items in the second list? -- Andrew (irc:RhodiumToad)
