hqx871 commented on a change in pull request #2363: URL: https://github.com/apache/calcite/pull/2363#discussion_r591201550
########## File path: core/src/test/java/org/apache/calcite/test/RelMetadataTest.java ########## @@ -3412,4 +3414,41 @@ public String colType(RelNode rel, int column) { assertThat(columnOrigin.getOriginTable().getRowType().getFieldNames().get(5), equalTo("SAL")); } + + // ---------------------------------------------------------------------- + // Tests for SortCpuCost + // ---------------------------------------------------------------------- + + @Test void testSortCpuCostOffsetLimit() { + final String sql = "select ename from emp order by ename limit 5 offset 5"; + double cpuCost = EMP_SIZE * Math.log(10) * 4; + checkCpuCost(sql, cpuCost); + } + + @Test void testSortCpuCostLimit() { + final String sql = "select ename from emp limit 10"; + checkCpuCost(sql, 0d); + } + + @Test void testSortCpuCostLimit0() { + final String sql = "select ename from emp order by ename limit 0"; + checkCpuCost(sql, 0d); + } + + @Test void testSortCpuCostLargeLimit() { + final String sql = "select ename from emp order by ename limit 10000"; + double cpuCost = EMP_SIZE * Math.log(EMP_SIZE) * 4; + checkCpuCost(sql, cpuCost); + } + + private void checkCpuCost(String sql, double expected) { + RelNode rel = convertSql(sql); + assertThat("query should be sort", rel instanceof LogicalSort); + final RelMetadataQuery mq = rel.getCluster().getMetadataQuery(); + RelOptPlanner planner = new VolcanoPlanner(); + RelOptCost cost = rel.computeSelfCost(planner, mq); + assertThat(cost, notNullValue()); Review comment: I know the cost won't be null, bu the ide warns me it could be. So I add the assert ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org