[CALCITE-1382] ClassCastException in JDBC Adapter

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.9.0
• Fix Version/s: 1.27.0
• Component/s: core
• Labels: adapters jdbc

Environment

This bug was detected using a postgresql database and the calcite version 1.9.0.

• Assignee: Julian Hyde
• Reporter: Miguel Oliveira
• Created: 22/Sep/16 18:17
• Updated: 03/Jun/21 22:31
• Resolved: 18/Dec/20 22:26

Description

This query:

SELECT count(*) FROM (SELECT count(emp.empno) `Count Emp`, dept.dname `Department Name` FROM Calcite.emp emp JOIN Calcite.dept dept ON emp.deptno = dept.deptno JOIN Calcite.salgrade salgrade ON emp.comm = salgrade.hisal WHERE dept.dname LIKE '%O%' GROUP BY emp.deptno, dept.dname)

generates a ClassCastException: "org.apache.calcite.adapter.jdbc.JdbcRules$JdbcJoin cannot be cast to org.apache.calcite.adapter.enumerable.EnumerableRel".

The plan is the following:

[TABLE, #ID {PLAN=EnumerableAggregate(group=[{}], EXPR$0=[COUNT()])
  EnumerableAggregate(group=[{2, 4}])
    JdbcJoin(condition=[=($1, $0)], joinType=[inner])
      JdbcProject(hisal=[$2])
        JdbcTableScan(table=[[Calcite, salgrade]])
      JdbcJoin(condition=[=($1, $2)], joinType=[inner])
        JdbcProject(comm=[$6], deptno=[$7])
          JdbcTableScan(table=[[Calcite, emp]])
        JdbcProject(deptno=[$0], dname=[$1])
          JdbcFilter(condition=[LIKE($1, '%O%')])
            JdbcTableScan(table=[[Calcite, dept]])
, }]

Runnable test:

/** Test case for
 * <a href="https://issues.apache.org/jira/browse/CALCITE-1382">[CALCITE-1382]
 * ClassCastException in JDBC adapter</a>. */
@org.junit.Test
public void testJoinPlan3() throws DataSourceManagerException {
    final String sql = "SELECT count(*) FROM (SELECT count(emp.empno) `Count Emp`, dept.dname `Department Name`\n"
            + "FROM emp emp JOIN dept dept ON emp.deptno = dept.deptno\n"
            + "JOIN salgrade salgrade ON emp.comm = salgrade.hisal\n"
            + "WHERE dept.dname LIKE '%A%' GROUP BY emp.deptno, dept.dname)";
    final String expected = "SELECT COUNT(*) FROM (\n" +
            "SELECT count(\"emp\".empno) AS \"Count Emp\", \"dept\".dname AS \"Department Name\"\n" +
            "FROM emp AS \"emp\"\n" +
            "INNER JOIN (\n" +
            "SELECT deptno, dname\n" +
            "FROM dept\n" +
            "WHERE dname LIKE '%A%'\n" +
            ") AS \"dept\" ON \"emp\".deptno = \"dept\".deptno\n" +
            "INNER JOIN (\n" +
            "SELECT hisal \n" +
            "FROM salgrade \n" +
            ") AS \"salgrade\" ON \"emp\".comm = \"salgrade\".hisal " +
            "GROUP BY \"emp\".deptno, \"dept\".dname" +
            ") AS \"t\"";
    sql(sql)
            .schema(CalciteAssert.SchemaSpec.JDBC_SCOTT)
            .ok(expected);
}

Issue Links

• is duplicated by: CALCITE-2015 Planner generates incompatible plan