| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.drill.jdbc.test; |
| |
| import static org.hamcrest.CoreMatchers.equalTo; |
| import static org.hamcrest.CoreMatchers.not; |
| import static org.hamcrest.MatcherAssert.assertThat; |
| |
| import java.sql.Connection; |
| import java.sql.DatabaseMetaData; |
| import java.sql.ResultSet; |
| import java.sql.ResultSetMetaData; |
| import java.sql.SQLException; |
| import java.sql.Statement; |
| |
| import org.apache.drill.jdbc.Driver; |
| import org.apache.drill.categories.JdbcTest; |
| import org.apache.drill.jdbc.JdbcTestBase; |
| import org.junit.AfterClass; |
| import org.junit.BeforeClass; |
| import org.junit.Test; |
| import org.junit.experimental.categories.Category; |
| |
| /** |
| * Tests from DRILL-2288, in which schema information wasn't propagated when a |
| * scan yielded an empty (zero-row) result set. |
| */ |
| @Category(JdbcTest.class) |
| public class Drill2288GetColumnsMetadataWhenNoRowsTest extends JdbcTestBase { |
| private static Connection connection; |
| |
| @BeforeClass |
| public static void setUpConnection() throws SQLException { |
| // (Note: Can't use JdbcTest's connect(...) because JdbcTest closes |
| // Connection--and other JDBC objects--on test method failure, but this test |
| // class uses some objects across methods.) |
| connection = new Driver().connect( "jdbc:drill:zk=local", JdbcTestBase.getDefaultProperties()); |
| } |
| |
| @AfterClass |
| public static void tearDownConnection() throws SQLException { |
| connection.close(); |
| } |
| |
| |
| /** |
| * Tests that an empty JSON file (having zero records) no longer triggers |
| * breakage in schema propagation. (Case failed before; columns a, b and c |
| * didn't show up.) |
| */ |
| @Test |
| public void testEmptyJsonFileDoesntSuppressNetSchema1() throws Exception { |
| Statement stmt = connection.createStatement(); |
| ResultSet results = stmt.executeQuery( "SELECT a, b, c, * FROM cp.`empty.json`" ); |
| |
| // Result set should still have columns even though there are no rows: |
| ResultSetMetaData metadata = results.getMetaData(); |
| assertThat( "ResultSetMetaData.getColumnCount() should have been > 0", |
| metadata.getColumnCount(), not( equalTo( 0 ) ) ); |
| |
| assertThat( "Unexpected non-empty results. Test rot?", |
| false, equalTo( results.next() ) ); |
| } |
| |
| @Test |
| public void testEmptyJsonFileDoesntSuppressNetSchema2() throws Exception { |
| Statement stmt = connection.createStatement(); |
| ResultSet results = stmt.executeQuery( "SELECT a FROM cp.`empty.json`" ); |
| |
| // Result set should still have columns even though there are no rows: |
| ResultSetMetaData metadata = results.getMetaData(); |
| assertThat( "ResultSetMetaData.getColumnCount() should have been 1", |
| metadata.getColumnCount(), equalTo( 1 ) ); |
| |
| assertThat( "Unexpected non-empty results. Test rot?", |
| false, equalTo( results.next() ) ); |
| } |
| |
| /** |
| * Tests that an INFORMATION_SCHEMA.TABLES query that has zero rows because of |
| * a (simple-enough) filter expression using column TABLE_SCHEMA (which |
| * supports pushdown) still has all columns. (Case failed before; had zero |
| * columns.) |
| */ |
| @Test |
| public void testInfoSchemaTablesZeroRowsBy_TABLE_SCHEMA_works() throws Exception { |
| Statement stmt = connection.createStatement(); |
| ResultSet results = |
| stmt.executeQuery( "SELECT * FROM INFORMATION_SCHEMA.`TABLES`" |
| + " WHERE TABLE_SCHEMA = ''" ); |
| |
| // Result set should still have columns even though there are no rows: |
| ResultSetMetaData metadata = results.getMetaData(); |
| assertThat( "ResultSetMetaData.getColumnCount() should have been > 0", |
| metadata.getColumnCount(), not( equalTo( 0 ) ) ); |
| |
| assertThat( "Unexpected non-empty results. Test rot?", |
| false, equalTo( results.next() ) ); |
| } |
| |
| /** (Worked before (because TABLE_CATALOG test not pushed down).) */ |
| @Test |
| public void testInfoSchemaTablesZeroRowsBy_TABLE_CATALOG_works() throws Exception { |
| Statement stmt = connection.createStatement(); |
| ResultSet results = |
| stmt.executeQuery( "SELECT * FROM INFORMATION_SCHEMA.`TABLES`" |
| + " WHERE TABLE_CATALOG = ''" ); |
| |
| // Result set should still have columns even though there are no rows: |
| ResultSetMetaData metadata = results.getMetaData(); |
| assertThat( "ResultSetMetaData.getColumnCount() should have been > 0", |
| metadata.getColumnCount(), not( equalTo( 0 ) ) ); |
| |
| assertThat( "Unexpected non-empty results. Test rot?", |
| false, equalTo( results.next() ) ); |
| } |
| |
| /** (Failed before (because TABLE_NAME test is pushed down).) */ |
| @Test |
| public void testInfoSchemaTablesZeroRowsBy_TABLE_NAME_works() |
| throws Exception { |
| Statement stmt = connection.createStatement(); |
| ResultSet results = |
| stmt.executeQuery( |
| "SELECT * FROM INFORMATION_SCHEMA.`TABLES` WHERE TABLE_NAME = ''" ); |
| |
| // Result set should still have columns even though there are no rows: |
| ResultSetMetaData metadata = results.getMetaData(); |
| assertThat( "ResultSetMetaData.getColumnCount() should have been > 0", |
| metadata.getColumnCount(), not( equalTo( 0 ) ) ); |
| |
| assertThat( "Unexpected non-empty results. Test rot?", |
| false, equalTo( results.next() ) ); |
| } |
| |
| /** (Worked before.) */ |
| @Test |
| public void testInfoSchemaTablesZeroRowsByLimitWorks() throws Exception { |
| Statement stmt = connection.createStatement(); |
| ResultSet results = |
| stmt.executeQuery( |
| "SELECT * FROM INFORMATION_SCHEMA.`TABLES` LIMIT 0" ); |
| |
| // Result set should still have columns even though there are no rows: |
| ResultSetMetaData metadata = results.getMetaData(); |
| assertThat( "ResultSetMetaData.getColumnCount() should have been > 0", |
| metadata.getColumnCount(), not( equalTo( 0 ) ) ); |
| |
| assertThat( "Unexpected non-empty results. Test rot?", |
| false, equalTo( results.next() ) ); |
| } |
| |
| /** (Worked before.) */ |
| @Test |
| public void testInfoSchemaTablesZeroRowsByWhereFalseWorks() throws Exception { |
| Statement stmt = connection.createStatement(); |
| ResultSet results = |
| stmt.executeQuery( |
| "SELECT * FROM INFORMATION_SCHEMA.`TABLES` WHERE FALSE" ); |
| |
| // Result set should still have columns even though there are no rows: |
| ResultSetMetaData metadata = results.getMetaData(); |
| assertThat( "ResultSetMetaData.getColumnCount() should have been > 0", |
| metadata.getColumnCount(), not( equalTo( 0 ) ) ); |
| |
| assertThat( "Unexpected non-empty results. Test rot?", |
| false, equalTo( results.next() ) ); |
| } |
| |
| /** (Failed before (because table schema and name tests are pushed down).) */ |
| @Test |
| public void testGetTablesZeroRowsByTableSchemaOrNameWorks() throws Exception { |
| DatabaseMetaData dbMetadata = connection.getMetaData(); |
| |
| ResultSet results = dbMetadata.getTables( "NoSuchCatalog", "NoSuchSchema", |
| "NoSuchTable", new String[0] ); |
| |
| // Result set should still have columns even though there are no rows: |
| ResultSetMetaData metadata = results.getMetaData(); |
| assertThat( "ResultSetMetaData.getColumnCount() should have been > 0", |
| metadata.getColumnCount(), not( equalTo( 0 ) ) ); |
| assertThat( "Unexpected non-empty results. Test rot?", |
| false, equalTo( results.next() ) ); |
| } |
| } |