From: Bjorn B. <bri...@cs...> - 2007-11-20 10:40:33
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On Nov 20, 2007, at 11:05 , Immanuel Normann wrote: > Hello, > > this is another try to get help about a question which I have send to > this mailing list about 2 weeks ago under the subject "Missing SQL > features". I haven't received any feedback may be because the =20 > traffic is > rather low in this mailing list - so I try again: > > I can't find the SQL operators exists (and join) in HaskellDB. Are =20 > they > not supported yet or have they different names here? > > Basically I need to express in HaskellDB something like: > > SELECT DISTINCT store_type FROM stores > WHERE NOT EXISTS (SELECT * FROM cities_stores > WHERE cities_stores.store_type =3D =20 > stores.store_type); > > (i.e. asking the question "What kind of store is present in no =20 > cities?") > > Any hints how to accomplish this in HaskellDB are highly appreciated. > > Thanks, > Immanuel Hi Immanuel, EXISTS is unfortunately not implemented yet. There are only inner =20 joins. Fixing these deficiencies would be very welcome. /Bj=F6rn |