Fully qualified column names
От | Dave Cramer |
---|---|
Тема | Fully qualified column names |
Дата | |
Msg-id | 00ce01c129d5$77769ec0$c201a8c0@inspiron обсуждение исходный текст |
Список | pgsql-hackers |
This is from the jdbc list. Is there any way to get fully qualified column names? Dave -----Original Message----- From: pgsql-jdbc-owner@postgresql.org [mailto:pgsql-jdbc-owner@postgresql.org] On Behalf Of Ben Carterette Sent: August 16, 2001 11:02 AM To: Rene Pijlman Cc: pgsql-jdbc@postgresql.org Subject: Re: [JDBC] select on multiple tables This won't work because I don't know in advance of the SELECT which tables I'm going to be selecting from. The SELECT is done in a servlet that determines the tables based on request parameters. I tried "SELECT table1.*, table2.* FROM table1, table2", but it still can't tell the difference between columns with the same name. Thanks for your help ben On Wednesday, August 15, 2001, at 06:29 PM, Rene Pijlman wrote: > On Wed, 15 Aug 2001 16:43:31 -0500, Ben Carterette wrote: >> I have a query like "SELECT * FROM table1, table2" and I want to read >> values out of a ResultSet. What if the two tables have column names >> in common and >> I can't predict the column numbers? Is there any way to get table1.id >> and >> table2.id? rs.getString tells me "The column name table1.id not >> found." > > Does this also happen when you explicitly name the columns? > > SELECT table1.id, ..., table2.id, ... > FROM table1, table2 > > Or if that doesn't help, try if a column label with the AS clause > works: > > SELECT [ ALL | DISTINCT [ ON ( expression [, ...] ) ] ] > * | expression [ AS output_name ] [, ...] > http://www.postgresql.org/idocs/index.php?sql-select.html > > SELECT table.id AS id1, ..., table2.id AS id2 > FROM table1, table2 > > And then rs.getString("id1"); > > I think both solutions should work. Please let us know if they don't. > > Regards, > René Pijlman > ---------------------------(end of broadcast)--------------------------- TIP 4: Don't 'kill -9' the postmaster
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