add pg testcase.

src/test/java/com/alibaba/druid/bvt/sql/postgresql/select/PGSelectTest43.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright 1999-2101 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.postgresql.select;
+
+import com.alibaba.druid.sql.PGTest;
+import com.alibaba.druid.sql.SQLUtils;
+import com.alibaba.druid.sql.ast.SQLStatement;
+import com.alibaba.druid.sql.dialect.postgresql.parser.PGSQLStatementParser;
+import com.alibaba.druid.sql.dialect.postgresql.visitor.PGSchemaStatVisitor;
+import org.junit.Assert;
+
+import java.util.List;
+
+public class PGSelectTest43 extends PGTest {
+
+    public void test_0() throws Exception {
+        String sql = "select task_id from mod_period_time where task_id in (SELECT task_id as b FROM mod_period_time order by task_id desc limit 1)";
+
+        PGSQLStatementParser parser = new PGSQLStatementParser(sql);
+        List<SQLStatement> statementList = parser.parseStatementList();
+        SQLStatement stmt = statementList.get(0);
+
+        Assert.assertEquals("SELECT task_id\n" +
+                "FROM mod_period_time\n" +
+                "WHERE task_id IN (SELECT task_id AS b\n" +
+                "\tFROM mod_period_time\n" +
+                "\tORDER BY task_id DESC\n" +
+                "\tLIMIT 1)", SQLUtils.toPGString(stmt));
+        
+        Assert.assertEquals("select task_id\n" +
+                "from mod_period_time\n" +
+                "where task_id in (select task_id as b\n" +
+                "\tfrom mod_period_time\n" +
+                "\torder by task_id desc\n" +
+                "\tlimit 1)", SQLUtils.toPGString(stmt, SQLUtils.DEFAULT_LCASE_FORMAT_OPTION));
+
+        Assert.assertEquals(1, statementList.size());
+
+        PGSchemaStatVisitor visitor = new PGSchemaStatVisitor();
+        stmt.accept(visitor);
+
+//        System.out.println("Tables : " + visitor.getTables());
+//        System.out.println("fields : " + visitor.getColumns());
+//        System.out.println("coditions : " + visitor.getConditions());
+
+        Assert.assertEquals(1, visitor.getColumns().size());
+        Assert.assertEquals(1, visitor.getTables().size());
+    }
+}