Re: How do you write this query?
От | Achilleus Mantzios |
---|---|
Тема | Re: How do you write this query? |
Дата | |
Msg-id | Pine.LNX.4.44.0211010949000.3526-100000@matrix.gatewaynet.com обсуждение исходный текст |
Ответ на | How do you write this query? (Wei Weng <wweng@kencast.com>) |
Список | pgsql-sql |
On 31 Oct 2002, Wei Weng wrote: and yet another equivalent query: SELECT f1.data1 from test f1,test f2 where f1.data=3 and f1.data2 = f2.data2 and f2.data1='pooh'; > I have a table > > Table "test" > Column | Type | Modifiers > --------+------------------------+---------- > data | integer | not null > data1 | character varying(128) | not null > data2 | character varying(128) | not null > > (Note: data is NOT the primary key.) > > And > select * from test > returns > > > data | data1 | data2 > ------+-------+------- > 1 | foo | bar > 2 | greg | bar > 3 | pooh | bar > 4 | dah | peng > > I need a query that returns me the "data1" that satisfies the logic of > the following pseudo code: > > 1: select data2 into @out from test where data1 = 'pooh' > 2: select data1 from test where data2 = @out and data = 3 > > > What do I do? > > Thanks! > > -- > Wei Weng > Network Software Engineer > KenCast Inc. > > > > ---------------------------(end of broadcast)--------------------------- > TIP 3: if posting/reading through Usenet, please send an appropriate > subscribe-nomail command to majordomo@postgresql.org so that your > message can get through to the mailing list cleanly > ================================================================== Achilleus Mantzios S/W Engineer IT dept Dynacom Tankers Mngmt Nikis 4, Glyfada Athens 16610 Greece tel: +30-10-8981112 fax: +30-10-8981877 email: achill@matrix.gatewaynet.com mantzios@softlab.ece.ntua.gr
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