无法调用 Java 中的存储过程

Question

I write a stored procedure in PostgreSQL . I try to use, this procedure in java, it throw ' org.postgresql.util.PSQLException: ERROR: cursor " < unnamed portal 1 > " does not exist ' exception.

procedure:

CREATE OR REPLACE FUNCTION subject_show(session_id CHARACTER VARYING,OUT result_cursor refcursor, OUT total_record INTEGER, OUT total_search_record INTEGER  ) AS $$
        BEGIN
            total_record:=23;
            total_search_record:=22;
            OPEN result_cursor FOR SELECT "ID","NAME"   FROM "SUBJECTS" ;
    END;
    $$ LANGUAGE plpgsql;

Call procedure, in java :

...

callableStatement = conn.prepareCall("{ call subject_show(?,?,?,?) }");
callableStatement.setString(1, sessionID);
callableStatement.registerOutParameter(2, Types.REF);
callableStatement.registerOutParameter(3, Types.INTEGER);
callableStatement.registerOutParameter(4, Types.INTEGER);
callableStatement.executeUpdate();
System.out.println(callableStatement.getObject(3));
System.out.println(callableStatement.getObject(4));
rs = (ResultSet) callableStatement.getObject(2);
...

Answer 1

I found that, I can only do this if you have autocommit turned off. Cursors are only valid within a transaction , thus as soon as the driver commits the cursor is no longer valid. Thus the error I am receiving.

Answer 2

I solved this in my code by adding @Transactional to the function