添加postgresql的begin，commit，set命令解析

添加PGStatement的测试代码，修复PGStatement解析bug;修复pg无法识别table别名问题

将PG的关键字移入TOKEN中

start transaction的visit优化

src/test/java/com/alibaba/druid/bvt/sql/postgresql/PGBeginTest.java

@@ -0,0 +1,32 @@
+/*
+ * 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.postgresql;
+
+import com.alibaba.druid.sql.PGTest;
+import com.alibaba.druid.sql.dialect.postgresql.ast.stmt.PGBeginStatement;
+
+public class PGBeginTest extends PGTest {
+    public void testBegin() throws Exception {
+        String sql = "begin;";
+        String expected = "BEGIN";
+        testParseSql(sql, expected, expected, PGBeginStatement.class);
+
+        sql = "start transaction;";
+        expected = "START TRANSACTION";
+        testParseSql(sql, expected, expected, PGBeginStatement.class);
+    }
+
+}

src/test/java/com/alibaba/druid/bvt/sql/postgresql/PGCommitTest.java

@@ -0,0 +1,27 @@
+/*
+ * 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.postgresql;
+
+import com.alibaba.druid.sql.PGTest;
+import com.alibaba.druid.sql.dialect.postgresql.ast.stmt.PGCommitStatement;
+
+public class PGCommitTest extends PGTest {
+    public void testCommit() throws Exception {
+        String sql = "commit;";
+        String expected = "COMMIT";
+        testParseSql(sql, expected, expected, PGCommitStatement.class);
+    }
+}

src/test/java/com/alibaba/druid/bvt/sql/postgresql/PGFromAsTest.java

@@ -0,0 +1,29 @@
+/*
+ * 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.postgresql;
+
+import com.alibaba.druid.sql.PGTest;
+import com.alibaba.druid.sql.dialect.postgresql.ast.stmt.PGSelectStatement;
+
+public class PGFromAsTest extends PGTest {
+    public void testFromAs() throws Exception {
+        String sql = "SELECT Count(*) FROM tb_abc AS t1 WHERE ((t1.a_id = 'global_a_id') AND (t1.owner = 'global_bc'));";
+        String expectedSql = "SELECT COUNT(*)\nFROM tb_abc t1\nWHERE t1.a_id = 'global_a_id'\n\tAND t1.owner = 'global_bc'";
+        String expectedPattern = "SELECT COUNT(*)\nFROM tb_abc t1\nWHERE t1.a_id = ?\n\tAND t1.owner = ?";
+        testParseSql(sql, expectedSql, expectedPattern, PGSelectStatement.class);
+    }
+
+}

src/test/java/com/alibaba/druid/bvt/sql/postgresql/PGSetTest3.java

@@ -0,0 +1,50 @@
+/*
+ * 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.postgresql;
+
+import com.alibaba.druid.sql.PGTest;
+import com.alibaba.druid.sql.dialect.postgresql.ast.stmt.PGSetStatement;
+
+public class PGSetTest3 extends PGTest {
+    public void testSet() throws Exception {
+        Class<?> type = PGSetStatement.class;
+
+        String sql = "SET TIME ZONE 'Europe/Rome';";
+        String expectedSql = "SET TIME ZONE 'Europe/Rome'";
+        String expectedPattern = "SET TIME ZONE ?";
+        testParseSql(sql, expectedSql, expectedPattern, type);
+
+        sql = "SET configuration_parameter TO DEFAULT;";
+        expectedSql = "SET configuration_parameter TO DEFAULT";
+        testParseSql(sql, expectedSql, expectedSql, type);
+
+        sql = "SET search_path TO my_schema, public;";
+        expectedSql = "SET search_path TO my_schema, public";
+        testParseSql(sql, expectedSql, expectedSql, type);
+
+        sql = "SET search_path =  my_schema, public;";
+        expectedSql = "SET search_path TO my_schema, public";
+        testParseSql(sql, expectedSql, expectedSql, type);
+
+        sql = "SET a=1";
+        expectedSql = "SET a TO 1";
+        testParseSql(sql, expectedSql, expectedSql, type);
+
+        sql = "SET a=1,2";
+        expectedSql = "SET a TO 1, 2";
+        testParseSql(sql, expectedSql, expectedSql, type);
+    }
+}

src/test/java/com/alibaba/druid/bvt/sql/postgresql/PGShowTest1.java

@@ -0,0 +1,31 @@
+/*
+ * 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.postgresql;
+
+import com.alibaba.druid.sql.PGTest;
+import com.alibaba.druid.sql.dialect.postgresql.ast.stmt.PGShowStatement;
+
+public class PGShowTest1 extends PGTest {
+    public void testShowAll() throws Exception {
+        String sql = "show all;";
+        String expected = "SHOW ALL";
+        testParseSql(sql, expected, expected, PGShowStatement.class);
+
+        sql = "show transaction_read_only;";
+        expected = "SHOW transaction_read_only";
+        testParseSql(sql, expected, expected, PGShowStatement.class);
+    }
+}

src/test/java/com/alibaba/druid/bvt/sql/postgresql/select/PGSelectTest42.java

@@ -33,13 +33,13 @@ public class PGSelectTest42 extends PGTest {
         List<SQLStatement> statementList = parser.parseStatementList();
         SQLStatement stmt = statementList.get(0);
 
-        Assert.assertEquals("UPDATE sys_account\n" +
+        Assert.assertEquals("UPDATE sys_account a\n" +
                 "SET online = 2\n" +
                 "FROM auto_handler_online o\n" +
                 "WHERE a.id = o.account_id\n" +
                 "\tAND a.online != 2", SQLUtils.toPGString(stmt));
         
-        Assert.assertEquals("update sys_account\n" +
+        Assert.assertEquals("update sys_account a\n" +
                 "set online = 2\n" +
                 "from auto_handler_online o\n" +
                 "where a.id = o.account_id\n" +

src/test/java/com/alibaba/druid/sql/PGTest.java

@@ -17,10 +17,12 @@ package com.alibaba.druid.sql;
 
 import java.util.List;
 
+import com.alibaba.druid.sql.dialect.postgresql.parser.PGSQLStatementParser;
 import junit.framework.TestCase;
 
 import com.alibaba.druid.sql.ast.SQLStatement;
 import com.alibaba.druid.sql.dialect.postgresql.visitor.PGOutputVisitor;
+import org.junit.Assert;
 
 public class PGTest extends TestCase {
 	protected String output(List<SQLStatement> stmtList) {
@@ -42,4 +44,18 @@ public class PGTest extends TestCase {
 	        }
 	        System.out.println(text);
 	    }
+
+    protected void testParseSql(String sql, String expectedSql, String expectedPattern, Class<?> type) {
+        PGSQLStatementParser parser = new PGSQLStatementParser(sql);
+        List<SQLStatement> statementList = parser.parseStatementList();
+        SQLStatement statement = statementList.get(0);
+
+        Assert.assertEquals(1, statementList.size());
+        Assert.assertTrue(type.isAssignableFrom(statement.getClass()));
+
+        StringBuilder sb = new StringBuilder();
+        PGOutputVisitor visitor = new PGOutputVisitor(sb);
+        statement.accept(visitor);
+        Assert.assertEquals(expectedSql, sb.toString());
+    }
 }