From: | Sferacarta Software <sferac(at)bo(dot)nettuno(dot)it> |
---|---|
To: | pgsql-hackers(at)postgresql(dot)org |
Subject: | gram.y |
Date: | 1998-12-03 12:22:45 |
Message-ID: | 15557.981203@bo.nettuno.it |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
Hi all,
I'm trying to make parser recognize SELECTs between parenthesis.
I need to do this work to have m$access working with PostgreSQL.
The micro$oft access jet (great wisdom) translates the UNIONs as:
(SELECT ...) UNION (SELECT ...)
To have PostgreSQL understand this syntax I edited gram.y
and I modified the "SelectStmt:" and the "SubUnion:" as:
SelectStmt: opt_left_paren SELECT
opt_unique
res_target_list2
result
from_clause
where_clause
group_clause
having_clause
opt_right_paren
union_clause
sort_clause
{
SelectStmt *n = makeNode(SelectStmt);
n->unique = $3;
n->targetList = $4;
n->into = $5;
n->fromClause = $6;
n->whereClause = $7;
n->groupClause = $8;
n->havingClause = $9;
n->unionClause = $11;
n->sortClause = $12;
$$ = (Node *)n;
}
;
SubUnion: opt_left_paren SELECT opt_unique res_target_list2
from_clause where_clause
group_clause having_clause opt_right_paren
{
SelectStmt *n = makeNode(SelectStmt);
n->unique = $3;
n->unionall = FALSE;
n->targetList = $4;
n->fromClause = $5;
n->whereClause = $6;
n->groupClause = $7;
n->havingClause = $8;
$$ = (Node *)n;
}
;
and now with these changes I can specify SELECTs inside () and
without parenthesis as before, I tried also subselects and seems that
all works well...but when I tried a select with a function which contains
parenthesis, like SUM(), VERSION() for example, then it doesn't work anymore.
I'm not very good programing in C.
Is there anybody that can help me with this question ?
Any help would be very appreciated.
EXAMPLES:
(select (2-3)*3);
?column?
--------
-3
(1 row)
(select (132-3)*3) union all ( select ((983+1)/2) );
?column?
--------
387
492
(2 rows)
select (132-3)*3 union all select ((983+1)/2);
?column?
--------
387
492
(2 rows)
select ename from emp where ename in (
select ename from emp where ename like 'K%'
);
ename
-----
KING
(1 row)
select version();
ERROR: parser: parse error at or near "("
-Jose'-
From | Date | Subject | |
---|---|---|---|
Next Message | Chris Williams | 1998-12-03 13:34:13 | Need immediate help with install |
Previous Message | Hiroshi Inoue | 1998-12-03 10:06:07 | Projecting attributes of function return values |