improve mysql ddl parser support

src/main/java/com/alibaba/druid/sql/dialect/mysql/parser/MySqlCreateTableParser.java

@@ -180,7 +180,7 @@ public class MySqlCreateTableParser extends SQLCreateTableParser {
                     if (lexer.token() == Token.EQ) {
                         lexer.nextToken();
                     }
-                    stmt.getTableOptions().put("CHARACTER SET", lexer.stringVal());
+                    stmt.getTableOptions().put("CHARSET", lexer.stringVal());
                     lexer.nextToken();
                 }
             }

src/main/java/com/alibaba/druid/sql/dialect/mysql/parser/MySqlStatementParser.java

@@ -2212,7 +2212,7 @@ public class MySqlStatementParser extends SQLStatementParser {
                         }
                         stmt.getItems().add(item);
                     }
-                } else if (identifierEquals("ALTER")) {
+                } else if (lexer.token() == Token.ALTER) {
                     throw new ParserException("TODO " + lexer.token() + " " + lexer.stringVal());
                 } else if (identifierEquals("CHANGE")) {
                     lexer.nextToken();

src/main/java/com/alibaba/druid/sql/dialect/mysql/visitor/MySqlSchemaStatVisitor.java

@@ -19,6 +19,8 @@ import java.util.Map;
 
 import com.alibaba.druid.sql.ast.SQLName;
 import com.alibaba.druid.sql.ast.expr.SQLIdentifierExpr;
+import com.alibaba.druid.sql.ast.statement.SQLAlterTableAddColumn;
+import com.alibaba.druid.sql.ast.statement.SQLAlterTableItem;
 import com.alibaba.druid.sql.ast.statement.SQLCreateTableStatement;
 import com.alibaba.druid.sql.ast.statement.SQLDropTableStatement;
 import com.alibaba.druid.sql.ast.statement.SQLExprTableSource;
@@ -245,8 +247,7 @@ public class MySqlSchemaStatVisitor extends SchemaStatVisitor implements MySqlAS
 
     @Override
     public boolean visit(MySqlKey x) {
-
-        return true;
+        return false;
     }
 
     @Override
@@ -1012,6 +1013,17 @@ public class MySqlSchemaStatVisitor extends SchemaStatVisitor implements MySqlAS
 
     @Override
     public boolean visit(MySqlAlterTableStatement x) {
+        String tableName = x.getName().toString();
+        TableStat stat = getTableStat(tableName);
+        stat.incrementAlterCount();
+
+        setCurrentTable(x, tableName);
+
+        for (SQLAlterTableItem item : x.getItems()) {
+            item.setParent(x);
+            item.accept(this);
+        }
+
         return false;
     }
 
@@ -1022,7 +1034,7 @@ public class MySqlSchemaStatVisitor extends SchemaStatVisitor implements MySqlAS
 
     @Override
     public boolean visit(MySqlAlterTableAddColumn x) {
-        return false;
+        return visit((SQLAlterTableAddColumn) x);
     }
 
     @Override
@@ -1209,4 +1221,5 @@ public class MySqlSchemaStatVisitor extends SchemaStatVisitor implements MySqlAS
     public void endVisit(MySqlAlterTableAddUnique x) {
         
     }
+    
 }

src/main/java/com/alibaba/druid/sql/visitor/SchemaStatVisitor.java

@@ -994,7 +994,7 @@ public class SchemaStatVisitor extends SQLASTVisitorAdapter {
     public boolean visit(SQLCurrentOfCursorExpr x) {
         return false;
     }
-
+    
     @Override
     public boolean visit(SQLAlterTableAddColumn x) {
         SQLAlterTableStatement stmt = (SQLAlterTableStatement) x.getParent();

src/main/java/com/alibaba/druid/stat/TableStat.java

@@ -445,7 +445,7 @@ public class TableStat {
     }
 
     public static enum Mode {
-        Insert(1), Update(2), Delete(4), Select(8), Merge(16), Truncate(32);
+        Insert(1), Update(2), Delete(4), Select(8), Merge(16), Truncate(32), Alter(64);
 
         public final int mark;
 

src/test/java/com/alibaba/druid/bvt/sql/mysql/MySqlAlterTableTest4.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright 1999-2011 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;
+
+import junit.framework.Assert;
+import junit.framework.TestCase;
+
+import com.alibaba.druid.sql.SQLUtils;
+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 com.alibaba.druid.sql.parser.Token;
+import com.alibaba.druid.stat.TableStat.Column;
+
+public class MySqlAlterTableTest4 extends TestCase {
+
+    public void test_alter_first() throws Exception {
+        String sql = "alter table test   add  dspcode  char(200)";
+        MySqlStatementParser parser = new MySqlStatementParser(sql);
+        SQLStatement stmt = parser.parseStatementList().get(0);
+        parser.match(Token.EOF);
+
+        MySqlSchemaStatVisitor visitor = new MySqlSchemaStatVisitor();
+        stmt.accept(visitor);
+
+        System.out.println("Tables : " + visitor.getTables());
+        System.out.println("fields : " + visitor.getColumns());
+        System.out.println("coditions : " + visitor.getConditions());
+        System.out.println("orderBy : " + visitor.getOrderByColumns());
+
+        String output = SQLUtils.toMySqlString(stmt);
+        Assert.assertEquals("ALTER TABLE test" + //
+                            "\n\tADD COLUMN dspcode char(200)", output);
+        
+        Assert.assertEquals(1, visitor.getTables().size());
+        Assert.assertEquals(1, visitor.getColumns().size());
+        Assert.assertTrue(visitor.getColumns().contains(new Column("test", "dspcode")));
+    }
+
+}

src/test/java/com/alibaba/druid/bvt/sql/mysql/MySqlAlterTableTest5.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright 1999-2011 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;
+
+import junit.framework.Assert;
+import junit.framework.TestCase;
+
+import com.alibaba.druid.sql.SQLUtils;
+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 com.alibaba.druid.sql.parser.Token;
+import com.alibaba.druid.stat.TableStat.Column;
+
+public class MySqlAlterTableTest5 extends TestCase {
+
+    public void test_alter_first() throws Exception {
+        String sql = "ALTER TABLE table_name   ALTER COLUMN column_name char(50)";
+        MySqlStatementParser parser = new MySqlStatementParser(sql);
+        SQLStatement stmt = parser.parseStatementList().get(0);
+        parser.match(Token.EOF);
+
+        MySqlSchemaStatVisitor visitor = new MySqlSchemaStatVisitor();
+        stmt.accept(visitor);
+
+        System.out.println("Tables : " + visitor.getTables());
+        System.out.println("fields : " + visitor.getColumns());
+        System.out.println("coditions : " + visitor.getConditions());
+        System.out.println("orderBy : " + visitor.getOrderByColumns());
+
+        String output = SQLUtils.toMySqlString(stmt);
+        Assert.assertEquals("ALTER TABLE test" + //
+                            "\n\tADD COLUMN dspcode char(200)", output);
+        
+        Assert.assertEquals(1, visitor.getTables().size());
+        Assert.assertEquals(1, visitor.getColumns().size());
+        Assert.assertTrue(visitor.getColumns().contains(new Column("test", "dspcode")));
+    }
+
+}

src/test/java/com/alibaba/druid/bvt/sql/mysql/MySqlCreateTableTest5.java

@@ -47,7 +47,7 @@ public class MySqlCreateTableTest5 extends MysqlTest {
         MySqlSchemaStatVisitor visitor = new MySqlSchemaStatVisitor();
         stmt.accept(visitor);
         
-        Assert.assertEquals("utf8", stmt.getTableOptions().get("CHARACTER SET"));
+        Assert.assertEquals("utf8", stmt.getTableOptions().get("CHARSET"));
 
         System.out.println("Tables : " + visitor.getTables());
         System.out.println("fields : " + visitor.getColumns());
@@ -55,7 +55,7 @@ public class MySqlCreateTableTest5 extends MysqlTest {
         System.out.println("orderBy : " + visitor.getOrderByColumns());
 
         Assert.assertEquals(1, visitor.getTables().size());
-        Assert.assertEquals(3, visitor.getColumns().size());
+        Assert.assertEquals(2, visitor.getColumns().size());
         Assert.assertEquals(0, visitor.getConditions().size());
 
         Assert.assertTrue(visitor.getTables().containsKey(new TableStat.Name("test")));