content: /*
   * Copyright 1999-2017 Alibaba Group Holding Ltd.
   *
   * Licensed 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 com.alibaba.druid.bvt.sql.mysql.select;
  
  import com.alibaba.druid.sql.MysqlTest;
  import com.alibaba.druid.sql.ast.SQLStatement;
  import com.alibaba.druid.sql.dialect.mysql.parser.MySqlStatementParser;
  import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlSchemaStatVisitor;
  
  import java.util.List;
  
  public class MySqlSelectTest_210_union extends MysqlTest {
      public void test_0() throws Exception {
          String sql = "SELECT count(*)\n" +
                  "FROM (\n" +
                  "  (SELECT user_id\n" +
                  "     FROM user_info_offline\n" +
                  "     WHERE create_time > '2018-01-01 00:00:00'\n" +
                  "     EXCEPT\n" +
                  "     SELECT user_id FROM user_info_online\n" +
                  "  )\n" +
                  "\n" +
                  "      UNION\n" +
                  "\n" +
                  "  SELECT coalesce(a.user_id, b.user_id) AS user_id\n" +
                  "      FROM user_info_online a LEFT JOIN user_info_offline b ON (a.user_id = b.user_id)\n" +
                  "      WHERE ((a.create_time > '2018-01-01 00:00:00') OR\n" +
                  "             (a.create_time IS NULL AND b.create_time > '2018-01-01 00:00:00')\n" +
                  "      )\n" +
                  ")";
  
          MySqlStatementParser parser = new MySqlStatementParser(sql);
          List<SQLStatement> statementList = parser.parseStatementList();
          SQLStatement stmt = statementList.get(0);
  
          assertEquals(1, statementList.size());
  
          assertEquals("SELECT count(*)\n" +
                          "FROM (\n" +
                          "\t(SELECT user_id\n" +
                          "\tFROM user_info_offline\n" +
                          "\tWHERE create_time > '2018-01-01 00:00:00'\n" +
                          "\tEXCEPT\n" +
                          "\tSELECT user_id\n" +
                          "\tFROM user_info_online)\n" +
                          "\tUNION\n" +
                          "\tSELECT coalesce(a.user_id, b.user_id) AS user_id\n" +
                          "\tFROM user_info_online a\n" +
                          "\t\tLEFT JOIN user_info_offline b ON (a.user_id = b.user_id)\n" +
                          "\tWHERE ((a.create_time > '2018-01-01 00:00:00')\n" +
                          "\t\tOR (a.create_time IS NULL\n" +
                          "\t\t\tAND b.create_time > '2018-01-01 00:00:00'))\n" +
                          ")", //
                  stmt.toString());
  
          MySqlSchemaStatVisitor visitor = new MySqlSchemaStatVisitor();
          stmt.accept(visitor);
  
          assertEquals(2, visitor.getTables().size());
          assertEquals(4, visitor.getColumns().size());
          assertEquals(5, visitor.getConditions().size());
          assertEquals(0, visitor.getOrderByColumns().size());
      }
  }
  