Josh Trutwin wrote: > > SELECT nspname as schema, c2.oid as tableoid, c2.relname as > > table, substring(pg_catalog.pg_get_indexdef(i.indexrelid, 0, true) > > from E'\\((.*)\\)') > 2.) Can you explain that substring line? What in the world is "from > E'\\((.*)\\)')" doing? Somehow it gets the column name.... The function is substring(foo from bar) so the E'' stuff you see is just the second operand. The E'' syntax allows backslash escapes; if you used '' without the E it would complain about the backslashes, because the SQL standard requires them to not mean escape characters, but in this case they are being treated as escapes. The first pair of backslashes are there to protect the parentheses from being turned them into capturing parens; they are doubled because the SQL parser eats one of them, so the regex engine really gets \((.*(\) which means "parens, then .*, then parens, but capture whatever is matched by the .*". Phew, I think this is a very confuse explanation. Hope it helps :-) -- Alvaro Herrera http://www.flickr.com/photos/alvherre/ "Aprender sin pensar es inútil; pensar sin aprender, peligroso" (Confucio) ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings
