Thread:
I am running into a behavior with a postgresql function with a SETOF refcursor's returning multiple columns. Not sure if there is a different way to retrieve a SETOF refcursor's with variable columns? Alternatively can I return a primitive value and a refcursor from the same function. I tried specifying this as OUT parameters without any luck. In Oracle you can pass this in functions:
Platform:
postgresql-x64-9.0 (PostgreSQL 9.0.1, compiled by Visual C++ build 1500, 64-bit)
Java1.6
JDBC4 Postgresql Driver, Version 9.0-801Function:
CREATE OR REPLACE FUNCTION test()
RETURNS SETOF refcursor AS
$BODY$
DECLARE
ref1 refcursor;
ref2 refcursor;
BEGIN
OPEN ref1 FOR SELECT 1;
RETURN NEXT ref1;
OPEN ref2 FOR SELECT 2, 3;
RETURN NEXT ref2;
RETURN;
END;
$BODY$
LANGUAGE plpgsql
Java Code:
CallableStatement cs = conn.prepareCall("{ call test() }");
ResultSet rs = cs.executeQuery();
while (rs.next()) {
System.out.println(rs.getString(1));
ResultSet rs2 = (ResultSet)rs.getObject(1);
while (rs2.next()) {
ResultSetMetaData rsmd = rs2.getMetaData();
int numberOfColumns = rsmd.getColumnCount();
System.out.println("numberOfColumns: " + numberOfColumns);
System.out.println(rs2.getString(1));
System.out.println(rs2.getString(2));
}
}
Output:
<unnamed portal 1>
numberOfColumns: 1
1
org.postgresql.util.PSQLException: The column index is out of range: 2, number of columns: 1.
at org.postgresql.jdbc2.AbstractJdbc2ResultSet.checkColumnIndex(AbstractJdbc2ResultSet.java:2680)
at org.postgresql.jdbc2.AbstractJdbc2ResultSet.checkResultSet(AbstractJdbc2ResultSet.java:2697)
at org.postgresql.jdbc2.AbstractJdbc2ResultSet.getString(AbstractJdbc2ResultSet.java:1872)
at PgBlob.test(PgBlob.java:64)
at PgBlob.main(PgBlob.java:37)
It appears the second result-set takes in the number of columns from the first irrespective of the number of columns from the second. If the change the function to return 2 refcursor's with same number of columns then it works as expected.
Function:
CREATE OR REPLACE FUNCTION test()
RETURNS SETOF refcursor AS
$BODY$
DECLARE
ref1 refcursor;
ref2 refcursor;
BEGIN
OPEN ref1 FOR SELECT 1, null;
RETURN NEXT ref1;
OPEN ref2 FOR SELECT 2, 3;
RETURN NEXT ref2;
RETURN;
END;
$BODY$
LANGUAGE plpgsql
Output:
<unnamed portal 1>
numberOfColumns: 2
1
4
<unnamed portal 2>
numberOfColumns: 2
2
3
Humair Mohammed <humairm@hotmail.com> writes:
> I am running into a behavior with a postgresql function with a SETOF refcursor's returning multiple columns. Not sure
ifthere is a different way to retrieve a SETOF refcursor's with variable columns? Alternatively can I return a
primitivevalue and a refcursor from the same function. I tried specifying this as OUT parameters without any luck. In
Oracleyou can pass this in functions:
> Platform:postgresql-x64-9.0 (PostgreSQL 9.0.1, compiled by Visual C++ build 1500, 64-bit)Java1.6JDBC4 Postgresql
Driver,Version 9.0-801
> Function:CREATE OR REPLACE FUNCTION test() RETURNS SETOF refcursor AS$BODY$DECLAREref1 refcursor;ref2
refcursor;BEGIN OPEN ref1 FOR SELECT 1; RETURN NEXT ref1; OPEN ref2 FOR SELECT 2, 3;
RETURNNEXT ref2; RETURN;END; $BODY$ LANGUAGE plpgsql
> Java Code:CallableStatement cs = conn.prepareCall("{ call test() }");ResultSet rs = cs.executeQuery();
> while (rs.next()) { System.out.println(rs.getString(1)); ResultSet rs2 = (ResultSet)rs.getObject(1); while
(rs2.next()){ ResultSetMetaData rsmd = rs2.getMetaData(); int numberOfColumns = rsmd.getColumnCount();
System.out.println("numberOfColumns: " + numberOfColumns); System.out.println(rs2.getString(1));
System.out.println(rs2.getString(2)); }}
> Output:<unnamed portal 1>numberOfColumns: 11org.postgresql.util.PSQLException: The column index is out of range: 2,
numberof columns: 1. at
org.postgresql.jdbc2.AbstractJdbc2ResultSet.checkColumnIndex(AbstractJdbc2ResultSet.java:2680) at
org.postgresql.jdbc2.AbstractJdbc2ResultSet.checkResultSet(AbstractJdbc2ResultSet.java:2697) at
org.postgresql.jdbc2.AbstractJdbc2ResultSet.getString(AbstractJdbc2ResultSet.java:1872) at
PgBlob.test(PgBlob.java:64) at PgBlob.main(PgBlob.java:37)
> It appears the second result-set takes in the number of columns from the first irrespective of the number of columns
fromthe second. If the change the function to return 2 refcursor's with same number of columns then it works as
expected.
> Function:CREATE OR REPLACE FUNCTION test() RETURNS SETOF refcursor AS$BODY$DECLAREref1 refcursor;ref2
refcursor;BEGIN OPEN ref1 FOR SELECT 1, null; RETURN NEXT ref1; OPEN ref2 FOR SELECT 2, 3;
RETURN NEXT ref2; RETURN;END; $BODY$ LANGUAGE plpgsql
> Output:<unnamed portal 1>numberOfColumns: 214<unnamed portal 2>numberOfColumns: 223
The example function works okay for me in psql. I think this is
actually a question about how to deal with such cases through the JDBC
driver, so I'd suggest asking on the pgsql-jdbc list. (Perhaps in a
less messy format this time, and could we ask for a useful Subject:
line too?)
regards, tom lane