Re: [HACKERS] Bug about column references within subqueries used in selects
NikhilS <[EMAIL PROTECTED]> writes: > Yes this is fine, but in "select columnname from tablename" using column > references of the other involved table is what I am objecting to. You can object till you're blue in the face, but this behavior is not changing because it's *required by spec*. Outer references are a standard and indeed essential part of SQL. regards, tom lane ---(end of broadcast)--- TIP 4: Have you searched our list archives? http://archives.postgresql.org
Re: [HACKERS] Bug about column references within subqueries used in selects
> > I don't think so...the columns of update_test are visible to the > scalar subquery...that way you can use fields from 'a' > to filter the > subquery... > select a, (select y from supdate_test where x = a) from > update_test; > > > Yes this is fine, but in "select columnname from tablename" > using column references of the other involved table is what I > am objecting to. > There's nothing here to object to, the system is acting correctly. Your column name "b" is ambiguous, and the system takes the column "b" that exists, rather than returning an error on a column that doesn't exist. If you were explicit in your column name, you would get an error: =# select a, (select supdate_test.b from supdate_test) from update_test; ERROR: No such attribute supdate_test.b Regards, Paul ---(end of broadcast)--- TIP 2: Don't 'kill -9' the postmaster
Re: [HACKERS] Bug about column references within subqueries used in selects
Hi, On 4/12/07, Merlin Moncure <[EMAIL PROTECTED]> wrote: On 4/12/07, NikhilS <[EMAIL PROTECTED]> wrote: > Hi, > > Shouldn't the final command below cause a 'column "b" does not exist error'? > > create table update_test (a int, b int); > create table supdate_test(x int, y int); > insert into update_test values (20, 30); > insert into supdate_test values (40, 50); > select a, (select b from supdate_test) from update_test; > > a ?column? > -- - > 2030 > > Is the problem with the code in colNameToVar or maybe we should add checks > in transformSubLink? I don't think so...the columns of update_test are visible to the scalar subquery...that way you can use fields from 'a' to filter the subquery... select a, (select y from supdate_test where x = a) from update_test; Yes this is fine, but in "select columnname from tablename" using column references of the other involved table is what I am objecting to. Regards, Nikhils -- EnterpriseDB http://www.enterprisedb.com
Re: [HACKERS] Bug about column references within subqueries used in selects
On 4/12/07, NikhilS <[EMAIL PROTECTED]> wrote: Hi, Shouldn't the final command below cause a 'column "b" does not exist error'? create table update_test (a int, b int); create table supdate_test(x int, y int); insert into update_test values (20, 30); insert into supdate_test values (40, 50); select a, (select b from supdate_test) from update_test; a ?column? -- - 2030 Is the problem with the code in colNameToVar or maybe we should add checks in transformSubLink? I don't think so...the columns of update_test are visible to the scalar subquery...that way you can use fields from 'a' to filter the subquery... select a, (select y from supdate_test where x = a) from update_test; merlin ---(end of broadcast)--- TIP 5: don't forget to increase your free space map settings
[HACKERS] Bug about column references within subqueries used in selects
Hi, Shouldn't the final command below cause a 'column "b" does not exist error'? create table update_test (a int, b int); create table supdate_test(x int, y int); insert into update_test values (20, 30); insert into supdate_test values (40, 50); select a, (select b from supdate_test) from update_test; a ?column? -- - 2030 Is the problem with the code in colNameToVar or maybe we should add checks in transformSubLink? Regards, Nikhils -- EnterpriseDB http://www.enterprisedb.com
