improved sql parser.

src/main/java/com/alibaba/druid/sql/ast/expr/SQLCharExpr.java

@@ -16,6 +16,7 @@
 package com.alibaba.druid.sql.ast.expr;
 
 import com.alibaba.druid.sql.SQLUtils;
+import com.alibaba.druid.sql.visitor.SQLASTOutputVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 
 public class SQLCharExpr extends SQLTextLiteralExpr implements SQLValuableExpr{
@@ -30,13 +31,11 @@ public class SQLCharExpr extends SQLTextLiteralExpr implements SQLValuableExpr{
 
     @Override
     public void output(StringBuffer buf) {
-        if ((this.text == null) || (this.text.length() == 0)) {
-            buf.append("NULL");
-        } else {
-            buf.append("'");
-            buf.append(this.text.replaceAll("'", "''"));
-            buf.append("'");
-        }
+        output((Appendable) buf);
+    }
+
+    public void output(Appendable buf) {
+        this.accept(new SQLASTOutputVisitor(buf));
     }
 
     protected void accept0(SQLASTVisitor visitor) {

src/main/java/com/alibaba/druid/sql/ast/statement/SQLAlterTableRename.java

@@ -16,6 +16,7 @@
 package com.alibaba.druid.sql.ast.statement;
 
 import com.alibaba.druid.sql.ast.SQLExpr;
+import com.alibaba.druid.sql.ast.SQLName;
 import com.alibaba.druid.sql.ast.SQLObjectImpl;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 
@@ -35,6 +36,20 @@ public class SQLAlterTableRename extends SQLObjectImpl implements SQLAlterTableI
         return to;
     }
 
+    public SQLName getToName() {
+        if (to == null) {
+            return null;
+        }
+
+        SQLExpr expr = to.expr;
+
+        if (expr instanceof SQLName) {
+            return (SQLName) expr;
+        }
+
+        return null;
+    }
+
     public void setTo(SQLExprTableSource to) {
         if (to != null) {
             to.setParent(this);

src/main/java/com/alibaba/druid/sql/ast/statement/SQLColumnDefinition.java

@@ -96,6 +96,14 @@ public class SQLColumnDefinition extends SQLObjectImpl implements SQLTableElemen
         return name;
     }
 
+    public String getNameAsString() {
+        if (name == null) {
+            return null;
+        }
+
+        return name.toString();
+    }
+
     public void setName(SQLName name) {
         this.name = name;
     }

src/main/java/com/alibaba/druid/sql/ast/statement/SQLCreateTableStatement.java

@@ -26,7 +26,6 @@ import com.alibaba.druid.sql.dialect.mysql.ast.MySqlKey;
 import com.alibaba.druid.sql.dialect.mysql.ast.MySqlUnique;
 import com.alibaba.druid.sql.dialect.mysql.ast.statement.MySqlTableIndex;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
-import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlShowColumnOutpuVisitor;
 import com.alibaba.druid.util.ListDG;
 import com.alibaba.druid.util.lang.Consumer;
 
@@ -263,27 +262,32 @@ public class SQLCreateTableStatement extends SQLStatementImpl implements SQLDDLS
 
     public SQLTableElement findIndex(String columnName) {
         for (SQLTableElement element : tableElementList) {
-            List<SQLExpr> keyColumns = null;
             if (element instanceof SQLUniqueConstraint) {
                 SQLUniqueConstraint unique = (SQLUniqueConstraint) element;
-                keyColumns = unique.getColumns();
+                for (SQLExpr columnExpr : unique.getColumns()) {
+                    if (columnExpr instanceof SQLIdentifierExpr) {
+                        String keyColumName = ((SQLIdentifierExpr) columnExpr).getName();
+                        keyColumName = SQLUtils.normalize(keyColumName);
+                        if (keyColumName.equalsIgnoreCase(columnName)) {
+                            return element;
+                        }
+                    }
+                }
+
             } else if (element instanceof MySqlTableIndex) {
-                keyColumns = ((MySqlTableIndex) element).getColumns();
-            }
-
-            if (keyColumns == null) {
-                continue;
-            }
-
-            for (SQLExpr columnExpr : keyColumns) {
-                if (columnExpr instanceof SQLIdentifierExpr) {
-                    String keyColumName = ((SQLIdentifierExpr) columnExpr).getName();
-                    keyColumName = SQLUtils.normalize(keyColumName);
-                    if (keyColumName.equalsIgnoreCase(columnName)) {
-                        return element;
+                List<SQLSelectOrderByItem> indexColumns = ((MySqlTableIndex) element).getColumns();
+                for (SQLSelectOrderByItem orderByItem : indexColumns) {
+                    SQLExpr columnExpr = orderByItem.getExpr();
+                    if (columnExpr instanceof SQLIdentifierExpr) {
+                        String keyColumName = ((SQLIdentifierExpr) columnExpr).getName();
+                        keyColumName = SQLUtils.normalize(keyColumName);
+                        if (keyColumName.equalsIgnoreCase(columnName)) {
+                            return element;
+                        }
                     }
                 }
             }
+
         }
 
         return null;
@@ -529,20 +533,153 @@ public class SQLCreateTableStatement extends SQLStatementImpl implements SQLDDLS
 
         int applyCount = 0;
         for (SQLAlterTableItem item : alter.getItems()) {
-            if (item instanceof SQLAlterTableDropColumnItem) {
-                if (apply((SQLAlterTableDropColumnItem) item)) {
-                    applyCount++;
-                }
-            } else if (item instanceof SQLAlterTableAddColumn) {
-                if (apply((SQLAlterTableAddColumn) item)) {
-                    applyCount++;
-                }
+            if (alterApply(item)) {
+                applyCount++;
             }
         }
 
         return applyCount > 0;
     }
 
+    protected boolean alterApply(SQLAlterTableItem item) {
+        if (item instanceof SQLAlterTableDropColumnItem) {
+            return apply((SQLAlterTableDropColumnItem) item);
+
+        } else if (item instanceof SQLAlterTableAddColumn) {
+            return apply((SQLAlterTableAddColumn) item);
+
+        } else if (item instanceof SQLAlterTableAddConstraint) {
+            return apply((SQLAlterTableAddConstraint) item);
+
+        } else if (item instanceof SQLAlterTableDropPrimaryKey) {
+            return apply((SQLAlterTableDropPrimaryKey) item);
+
+        } else if (item instanceof SQLAlterTableDropIndex) {
+            return apply((SQLAlterTableDropIndex) item);
+
+        } else if (item instanceof SQLAlterTableDropConstraint) {
+            return apply((SQLAlterTableDropConstraint) item);
+
+        } else if (item instanceof SQLAlterTableDropKey) {
+            return apply((SQLAlterTableDropKey) item);
+
+        } else if (item instanceof SQLAlterTableDropForeignKey) {
+            return apply((SQLAlterTableDropForeignKey) item);
+
+        } else if (item instanceof SQLAlterTableRename) {
+            return apply((SQLAlterTableRename) item);
+
+        } else if (item instanceof SQLAlterTableRenameColumn) {
+            return apply((SQLAlterTableRenameColumn) item);
+        }
+
+        return false;
+    }
+
+    // SQLAlterTableRenameColumn
+
+    private boolean apply(SQLAlterTableRenameColumn item) {
+        int columnIndex = columnIndexOf(item.getColumn());
+        if (columnIndex == -1) {
+            return false;
+        }
+
+        SQLColumnDefinition column = (SQLColumnDefinition) tableElementList.get(columnIndex);
+        column.setName(item.getTo().clone());
+
+        return true;
+    }
+
+    private boolean apply(SQLAlterTableRename item) {
+        SQLName name = item.getToName();
+        if (name == null) {
+            return false;
+        }
+
+        this.setName(name.clone());
+
+        return true;
+    }
+
+    private boolean apply(SQLAlterTableDropForeignKey item) {
+        for (int i = tableElementList.size() - 1; i >= 0; i--) {
+            SQLTableElement e = tableElementList.get(i);
+            if (e instanceof SQLUniqueConstraint) {
+                SQLForeignKeyConstraint fk = (SQLForeignKeyConstraint) e;
+                if (SQLUtils.nameEquals(fk.getName(), item.getIndexName())) {
+                    tableElementList.remove(i);
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+
+    private boolean apply(SQLAlterTableDropKey item) {
+        for (int i = tableElementList.size() - 1; i >= 0; i--) {
+            SQLTableElement e = tableElementList.get(i);
+            if (e instanceof SQLUniqueConstraint) {
+                SQLUniqueConstraint unique = (SQLUniqueConstraint) e;
+                if (SQLUtils.nameEquals(unique.getName(), item.getKeyName())) {
+                    tableElementList.remove(i);
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+
+    private boolean apply(SQLAlterTableDropConstraint item) {
+        for (int i = tableElementList.size() - 1; i >= 0; i--) {
+            SQLTableElement e = tableElementList.get(i);
+            if (e instanceof SQLConstraint) {
+                SQLConstraint constraint = (SQLConstraint) e;
+                if (SQLUtils.nameEquals(constraint.getName(), item.getConstraintName())) {
+                    tableElementList.remove(i);
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+
+    private boolean apply(SQLAlterTableDropIndex item) {
+        for (int i = tableElementList.size() - 1; i >= 0; i--) {
+            SQLTableElement e = tableElementList.get(i);
+            if (e instanceof SQLUniqueConstraint) {
+                SQLUniqueConstraint unique = (SQLUniqueConstraint) e;
+                if (SQLUtils.nameEquals(unique.getName(), item.getIndexName())) {
+                    tableElementList.remove(i);
+                    return true;
+                }
+
+            } else if (e instanceof MySqlTableIndex) {
+                MySqlTableIndex tableIndex = (MySqlTableIndex) e;
+                if (SQLUtils.nameEquals(tableIndex.getName(), item.getIndexName())) {
+                    tableElementList.remove(i);
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+
+    private boolean apply(SQLAlterTableDropPrimaryKey item) {
+        for (int i = tableElementList.size() - 1; i >= 0; i--) {
+            SQLTableElement e = tableElementList.get(i);
+            if (e instanceof SQLPrimaryKey) {
+                tableElementList.remove(i);
+                return true;
+            }
+        }
+        return false;
+    }
+
+    private boolean apply(SQLAlterTableAddConstraint item) {
+        tableElementList.add((SQLTableElement) item.getConstraint());
+        return true;
+    }
+
     private boolean apply(SQLAlterTableDropColumnItem item) {
         for (SQLName column : item.getColumns()) {
             String columnName = column.getSimpleName();
@@ -583,7 +720,7 @@ public class SQLCreateTableStatement extends SQLStatementImpl implements SQLDDLS
         return true;
     }
 
-    private int columnIndexOf(SQLName column) {
+    protected int columnIndexOf(SQLName column) {
         if (column == null) {
             return -1;
         }

src/main/java/com/alibaba/druid/sql/dialect/mysql/ast/MySqlUnique.java

@@ -18,7 +18,7 @@ package com.alibaba.druid.sql.dialect.mysql.ast;
 import com.alibaba.druid.sql.ast.statement.SQLPrimaryKey;
 import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlASTVisitor;
 
-public class MySqlUnique extends MySqlKey implements SQLPrimaryKey {
+public class MySqlUnique extends MySqlKey {
 
     public MySqlUnique(){
 

src/main/java/com/alibaba/druid/sql/dialect/mysql/ast/statement/MySqlAlterTableChangeColumn.java

@@ -30,8 +30,8 @@ public class MySqlAlterTableChangeColumn extends MySqlObjectImpl implements SQLA
 
     private boolean             first;
 
-    private SQLExpr             firstColumn;
-    private SQLExpr             afterColumn;
+    private SQLName             firstColumn;
+    private SQLName             afterColumn;
 
     @Override
     public void accept0(MySqlASTVisitor visitor) {
@@ -44,19 +44,19 @@ public class MySqlAlterTableChangeColumn extends MySqlObjectImpl implements SQLA
         }
     }
 
-    public SQLExpr getFirstColumn() {
+    public SQLName getFirstColumn() {
         return firstColumn;
     }
 
-    public void setFirstColumn(SQLExpr firstColumn) {
+    public void setFirstColumn(SQLName firstColumn) {
         this.firstColumn = firstColumn;
     }
 
-    public SQLExpr getAfterColumn() {
+    public SQLName getAfterColumn() {
         return afterColumn;
     }
 
-    public void setAfterColumn(SQLExpr afterColumn) {
+    public void setAfterColumn(SQLName afterColumn) {
         this.afterColumn = afterColumn;
     }
 

src/main/java/com/alibaba/druid/sql/dialect/mysql/ast/statement/MySqlAlterTableModifyColumn.java

@@ -16,6 +16,7 @@
 package com.alibaba.druid.sql.dialect.mysql.ast.statement;
 
 import com.alibaba.druid.sql.ast.SQLExpr;
+import com.alibaba.druid.sql.ast.SQLName;
 import com.alibaba.druid.sql.ast.statement.SQLAlterTableItem;
 import com.alibaba.druid.sql.ast.statement.SQLColumnDefinition;
 import com.alibaba.druid.sql.dialect.mysql.ast.MySqlObjectImpl;
@@ -27,8 +28,8 @@ public class MySqlAlterTableModifyColumn extends MySqlObjectImpl implements SQLA
 
     private boolean             first;
 
-    private SQLExpr             firstColumn;
-    private SQLExpr             afterColumn;
+    private SQLName             firstColumn;
+    private SQLName             afterColumn;
 
     @Override
     public void accept0(MySqlASTVisitor visitor) {
@@ -40,19 +41,19 @@ public class MySqlAlterTableModifyColumn extends MySqlObjectImpl implements SQLA
         }
     }
 
-    public SQLExpr getFirstColumn() {
+    public SQLName getFirstColumn() {
         return firstColumn;
     }
 
-    public void setFirstColumn(SQLExpr firstColumn) {
+    public void setFirstColumn(SQLName firstColumn) {
         this.firstColumn = firstColumn;
     }
 
-    public SQLExpr getAfterColumn() {
+    public SQLName getAfterColumn() {
         return afterColumn;
     }
 
-    public void setAfterColumn(SQLExpr afterColumn) {
+    public void setAfterColumn(SQLName afterColumn) {
         this.afterColumn = afterColumn;
     }
 

src/main/java/com/alibaba/druid/sql/dialect/mysql/ast/statement/MySqlAlterTableOption.java

@@ -15,6 +15,8 @@
  */
 package com.alibaba.druid.sql.dialect.mysql.ast.statement;
 
+import com.alibaba.druid.sql.ast.SQLObject;
+import com.alibaba.druid.sql.ast.expr.SQLIdentifierExpr;
 import com.alibaba.druid.sql.ast.statement.SQLAlterTableItem;
 import com.alibaba.druid.sql.dialect.mysql.ast.MySqlObjectImpl;
 import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlASTVisitor;
@@ -22,11 +24,15 @@ import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlASTVisitor;
 public class MySqlAlterTableOption extends MySqlObjectImpl implements SQLAlterTableItem {
 
     private String name;
-    private Object value;
+    private SQLObject value;
 
-    public MySqlAlterTableOption(String name, Object value){
+    public MySqlAlterTableOption(String name, String value){
+        this(name, new SQLIdentifierExpr(value));
+    }
+
+    public MySqlAlterTableOption(String name, SQLObject value){
         this.name = name;
-        this.value = value;
+        this.setValue(value);
     }
 
     public MySqlAlterTableOption(){
@@ -46,11 +52,11 @@ public class MySqlAlterTableOption extends MySqlObjectImpl implements SQLAlterTa
         this.name = name;
     }
 
-    public Object getValue() {
+    public SQLObject getValue() {
         return value;
     }
 
-    public void setValue(Object value) {
+    public void setValue(SQLObject value) {
         this.value = value;
     }
 

src/main/java/com/alibaba/druid/sql/dialect/mysql/ast/statement/MySqlCreateTableStatement.java

@@ -27,11 +27,10 @@ import com.alibaba.druid.sql.ast.SQLExpr;
 import com.alibaba.druid.sql.ast.SQLName;
 import com.alibaba.druid.sql.ast.SQLObject;
 import com.alibaba.druid.sql.ast.SQLPartitionBy;
-import com.alibaba.druid.sql.ast.statement.SQLCreateTableStatement;
-import com.alibaba.druid.sql.ast.statement.SQLExprTableSource;
-import com.alibaba.druid.sql.ast.statement.SQLSelect;
+import com.alibaba.druid.sql.ast.statement.*;
 import com.alibaba.druid.sql.dialect.mysql.ast.MySqlObjectImpl;
 import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlASTVisitor;
+import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlOutputVisitor;
 import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlShowColumnOutpuVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 import com.alibaba.druid.util.JdbcConstants;
@@ -192,6 +191,57 @@ public class MySqlCreateTableStatement extends SQLCreateTableStatement implement
         return false;
     }
 
+    protected boolean alterApply(SQLAlterTableItem item) {
+        if (item instanceof MySqlAlterTableAlterColumn) {
+            return apply((MySqlAlterTableAlterColumn) item);
+
+        } else if (item instanceof MySqlAlterTableChangeColumn) {
+            return apply((MySqlAlterTableChangeColumn) item);
+
+        } else if (item instanceof MySqlAlterTableCharacter) {
+            return apply((MySqlAlterTableCharacter) item);
+
+        } else if (item instanceof MySqlAlterTableModifyColumn) {
+            return apply((MySqlAlterTableModifyColumn) item);
+
+        } else if (item instanceof MySqlAlterTableOption) {
+            return apply((MySqlAlterTableOption) item);
+        }
+
+        return super.alterApply(item);
+    }
+
+    public boolean apply(SQLAlterTableAddIndex x) {
+        MySqlTableIndex index = new MySqlTableIndex();
+
+        index.setName(x.getName());
+        for (SQLSelectOrderByItem orderByItem : x.getItems()) {
+            index.addColumn(orderByItem.clone());
+        }
+        index.setParent(this);
+        this.tableElementList.add(index);
+
+        return true;
+    }
+
+    public boolean apply(MySqlAlterTableOption item) {
+        this.tableOptions.put(item.getName(), item.getValue());
+        return true;
+    }
+
+    public boolean apply(MySqlAlterTableCharacter item) {
+        SQLExpr charset = item.getCharacterSet();
+        if (charset != null) {
+            this.tableOptions.put("CHARACTER SET", charset);
+        }
+
+        SQLExpr collate = item.getCollate();
+        if (collate != null) {
+            this.tableOptions.put("COLLATE", collate);
+        }
+        return true;
+    }
+
     public boolean apply(MySqlRenameTableStatement.Item item) {
         if (!SQLUtils.nameEquals((SQLName) item.getName(), this.getName())) {
             return false;
@@ -199,4 +249,97 @@ public class MySqlCreateTableStatement extends SQLCreateTableStatement implement
         this.setName((SQLName) item.getTo().clone());
         return true;
     }
+
+    public boolean apply(MySqlAlterTableAlterColumn x) {
+        int columnIndex = columnIndexOf(x.getColumn());
+        if (columnIndex == -1) {
+            return false;
+        }
+
+        SQLExpr defaultExpr = x.getDefaultExpr();
+        SQLColumnDefinition column = (SQLColumnDefinition) tableElementList.get(columnIndex);
+
+        if (x.isDropDefault()) {
+            column.setDefaultExpr(null);
+        } else if (defaultExpr != null) {
+            column.setDefaultExpr(defaultExpr);
+        }
+
+        return true;
+    }
+
+    public boolean apply(MySqlAlterTableChangeColumn item) {
+        SQLName columnName = item.getColumnName();
+        int columnIndex = columnIndexOf(columnName);
+        if (columnIndex == -1) {
+            return false;
+        }
+
+        int afterIndex = columnIndexOf(item.getAfterColumn());
+        int beforeIndex = columnIndexOf(item.getFirstColumn());
+
+        int insertIndex = -1;
+        if (beforeIndex != -1) {
+            insertIndex = beforeIndex;
+        } else if (afterIndex != -1) {
+            insertIndex = afterIndex + 1;
+        }
+
+        SQLColumnDefinition column = item.getNewColumnDefinition().clone();
+        column.setParent(this);
+        if (insertIndex == -1 || insertIndex == columnIndex) {
+            tableElementList.set(columnIndex, column);
+            return true;
+        } else {
+            if (insertIndex > columnIndex) {
+                tableElementList.add(insertIndex, column);
+                tableElementList.remove(columnIndex);
+            } else {
+                tableElementList.remove(columnIndex);
+                tableElementList.add(insertIndex, column);
+            }
+        }
+
+        return true;
+    }
+
+    public boolean apply(MySqlAlterTableModifyColumn item) {
+        SQLColumnDefinition column = item.getNewColumnDefinition().clone();
+        SQLName columnName = column.getName();
+
+        int columnIndex = columnIndexOf(columnName);
+        if (columnIndex == -1) {
+            return false;
+        }
+
+        int afterIndex = columnIndexOf(item.getAfterColumn());
+        int beforeIndex = columnIndexOf(item.getFirstColumn());
+
+        int insertIndex = -1;
+        if (beforeIndex != -1) {
+            insertIndex = beforeIndex;
+        } else if (afterIndex != -1) {
+            insertIndex = afterIndex + 1;
+        }
+
+        column.setParent(this);
+        if (insertIndex == -1 || insertIndex == columnIndex) {
+            tableElementList.set(columnIndex, column);
+            return true;
+        } else {
+            if (insertIndex > columnIndex) {
+                tableElementList.add(insertIndex, column);
+                tableElementList.remove(columnIndex);
+            } else {
+                tableElementList.remove(columnIndex);
+                tableElementList.add(insertIndex, column);
+            }
+        }
+
+        return true;
+    }
+
+    public void output(StringBuffer buf) {
+        this.accept(new MySqlOutputVisitor(buf));
+    }
 }

src/main/java/com/alibaba/druid/sql/dialect/mysql/ast/statement/MySqlShowCreateTableStatement.java

@@ -16,11 +16,12 @@
 package com.alibaba.druid.sql.dialect.mysql.ast.statement;
 
 import com.alibaba.druid.sql.ast.SQLExpr;
+import com.alibaba.druid.sql.ast.SQLName;
 import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlASTVisitor;
 
 public class MySqlShowCreateTableStatement extends MySqlStatementImpl implements MySqlShowStatement {
 
-    private SQLExpr name;
+    private SQLName name;
 
     public void accept0(MySqlASTVisitor visitor) {
         if (visitor.visit(this)) {
@@ -29,11 +30,11 @@ public class MySqlShowCreateTableStatement extends MySqlStatementImpl implements
         visitor.endVisit(this);
     }
 
-    public SQLExpr getName() {
+    public SQLName getName() {
         return name;
     }
 
-    public void setName(SQLExpr name) {
+    public void setName(SQLName name) {
         if (name != null) {
             name.setParent(this);
         }

src/main/java/com/alibaba/druid/sql/dialect/mysql/ast/statement/MySqlTableIndex.java

@@ -20,6 +20,7 @@ import java.util.List;
 
 import com.alibaba.druid.sql.ast.SQLExpr;
 import com.alibaba.druid.sql.ast.SQLName;
+import com.alibaba.druid.sql.ast.statement.SQLSelectOrderByItem;
 import com.alibaba.druid.sql.ast.statement.SQLTableElement;
 import com.alibaba.druid.sql.dialect.mysql.ast.MySqlObjectImpl;
 import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlASTVisitor;
@@ -28,7 +29,7 @@ public class MySqlTableIndex extends MySqlObjectImpl implements SQLTableElement
 
     private SQLName       name;
     private String        indexType;
-    private List<SQLExpr> columns = new ArrayList<SQLExpr>();
+    private List<SQLSelectOrderByItem> columns = new ArrayList<SQLSelectOrderByItem>();
 
     public MySqlTableIndex(){
 
@@ -50,11 +51,11 @@ public class MySqlTableIndex extends MySqlObjectImpl implements SQLTableElement
         this.name = name;
     }
 
-    public List<SQLExpr> getColumns() {
+    public List<SQLSelectOrderByItem> getColumns() {
         return columns;
     }
     
-    public void addColumn(SQLExpr column) {
+    public void addColumn(SQLSelectOrderByItem column) {
         if (column != null) {
             column.setParent(this);
         }

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

@@ -140,7 +140,7 @@ public class MySqlCreateTableParser extends SQLCreateTableParser {
 
                         accept(Token.LPAREN);
                         for (;;) {
-                            idx.addColumn(this.exprParser.expr());
+                            idx.addColumn(this.exprParser.parseSelectOrderByItem());
                             if (!(lexer.token() == (Token.COMMA))) {
                                 break;
                             } else {

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

@@ -2843,7 +2843,7 @@ public class MySqlStatementParser extends SQLStatementParser {
             } else if (identifierEquals(AUTO_INCREMENT)) {
                 lexer.nextToken();
                 accept(Token.EQ);
-                stmt.addItem(new MySqlAlterTableOption(AUTO_INCREMENT, lexer.integerValue()));
+                stmt.addItem(new MySqlAlterTableOption(AUTO_INCREMENT, new SQLIntegerExpr(lexer.integerValue())));
                 lexer.nextToken();
             } else if (identifierEquals(COLLATE2)) {
                 lexer.nextToken();

src/main/java/com/alibaba/druid/sql/repository/Schema.java

@@ -24,8 +24,12 @@ import com.alibaba.druid.sql.ast.expr.SQLAllColumnExpr;
 import com.alibaba.druid.sql.ast.expr.SQLIdentifierExpr;
 import com.alibaba.druid.sql.ast.expr.SQLPropertyExpr;
 import com.alibaba.druid.sql.ast.statement.*;
+import com.alibaba.druid.sql.dialect.mysql.ast.statement.MySqlCreateTableStatement;
+import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlASTVisitorAdapter;
 import com.alibaba.druid.sql.dialect.oracle.ast.stmt.OracleCreateTableStatement;
 import com.alibaba.druid.sql.dialect.oracle.visitor.OracleASTVisitorAdapter;
+import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 import java.util.LinkedHashMap;
 import java.util.List;
@@ -42,12 +46,18 @@ public class Schema {
 
     private final Map<String, SchemaObject> functions  = new ConcurrentSkipListMap<String, SchemaObject>();
 
-    private final Schema.SchemaVisitor visitor = new Schema.SchemaVisitor();
+    private final SQLASTVisitor visitor;
 
     private SchemaRepository repository;
 
     public Schema(SchemaRepository repository) {
         this.repository = repository;
+
+        if (JdbcConstants.MYSQL.equals(repository.dbType)) {
+            visitor = new MySqlSchemaVisitor();
+        } else {
+            visitor = new OracleSchemaVisitor();
+        }
     }
 
     public String getName() {
@@ -59,7 +69,6 @@ public class Schema {
     }
 
 
-
     public SchemaObject findTable(String tableName) {
         String lowerName = tableName.toLowerCase();
         SchemaObject object = objects.get(lowerName);
@@ -109,7 +118,7 @@ public class Schema {
                 && object.getType() == SchemaObjectType.Sequence;
     }
 
-    public class SchemaVisitor extends OracleASTVisitorAdapter {
+    public class OracleSchemaVisitor extends OracleASTVisitorAdapter {
 
         public boolean visit(SQLDropSequenceStatement x) {
             String name = x.getName().getSimpleName();
@@ -175,6 +184,72 @@ public class Schema {
         }
     }
 
+    private class MySqlSchemaVisitor extends MySqlASTVisitorAdapter {
+
+        public boolean visit(SQLDropSequenceStatement x) {
+            String name = x.getName().getSimpleName();
+            objects.remove(name);
+            return false;
+        }
+
+        public boolean visit(SQLCreateSequenceStatement x) {
+            String name = x.getName().getSimpleName();
+            SchemaObject object = new SchemaObjectImpl(name, SchemaObjectType.Sequence);
+
+            objects.put(name.toLowerCase(), object);
+            return false;
+        }
+
+        public boolean visit(MySqlCreateTableStatement x) {
+            visit((SQLCreateTableStatement) x);
+            return false;
+        }
+
+        public boolean visit(SQLCreateTableStatement x) {
+            String name = x.computeName();
+            SchemaObject object = new SchemaObjectImpl(name, SchemaObjectType.Table, x);
+
+            String name_lower = name.toLowerCase();
+            if (objects.containsKey(name_lower)) {
+                return false;
+            }
+            objects.put(name_lower, object);
+
+            return false;
+        }
+
+        public boolean visit(SQLCreateViewStatement x) {
+            String name = x.computeName();
+            SchemaObject object = new SchemaObjectImpl(name, SchemaObjectType.View, x);
+
+            String name_lower = name.toLowerCase();
+            if (objects.containsKey(name_lower)) {
+                return false;
+            }
+            objects.put(name_lower, object);
+
+            return false;
+        }
+
+        public boolean visit(SQLCreateIndexStatement x) {
+            String name = x.getName().getSimpleName();
+            SchemaObject object = new SchemaObjectImpl(name, SchemaObjectType.Index);
+
+            objects.put(name.toLowerCase(), object);
+
+            return false;
+        }
+
+        public boolean visit(SQLCreateFunctionStatement x) {
+            String name = x.getName().getSimpleName();
+            SchemaObject object = new SchemaObjectImpl(name, SchemaObjectType.Function, x);
+
+            functions.put(name.toLowerCase(), object);
+
+            return false;
+        }
+    }
+
     public SchemaObject findTable(SQLTableSource tableSource, String alias) {
         if (tableSource instanceof SQLExprTableSource) {
             if (alias.equalsIgnoreCase(tableSource.computeAlias())) {

src/main/java/com/alibaba/druid/sql/repository/SchemaRepository.java

@@ -15,6 +15,7 @@
  */
 package com.alibaba.druid.sql.repository;
 
+import com.alibaba.druid.DruidRuntimeException;
 import com.alibaba.druid.sql.SQLUtils;
 import com.alibaba.druid.sql.ast.SQLExpr;
 import com.alibaba.druid.sql.ast.SQLName;
@@ -24,9 +25,14 @@ import com.alibaba.druid.sql.ast.expr.SQLAllColumnExpr;
 import com.alibaba.druid.sql.ast.expr.SQLIdentifierExpr;
 import com.alibaba.druid.sql.ast.expr.SQLPropertyExpr;
 import com.alibaba.druid.sql.ast.statement.*;
+import com.alibaba.druid.sql.dialect.mysql.ast.statement.MySqlCreateTableStatement;
+import com.alibaba.druid.sql.dialect.mysql.ast.statement.MySqlShowColumnsStatement;
+import com.alibaba.druid.sql.dialect.mysql.ast.statement.MySqlShowCreateTableStatement;
 import com.alibaba.druid.sql.dialect.oracle.ast.stmt.OracleCreateTableStatement;
 import com.alibaba.druid.sql.dialect.oracle.visitor.OracleASTVisitorAdapter;
+import com.alibaba.druid.util.JdbcUtils;
 
+import java.io.IOException;
 import java.util.Collection;
 import java.util.LinkedHashMap;
 import java.util.List;
@@ -38,6 +44,15 @@ import java.util.concurrent.ConcurrentSkipListMap;
  */
 public class SchemaRepository {
     private Schema defaultSchema;
+    protected String dbType;
+
+    public SchemaRepository() {
+
+    }
+
+    public SchemaRepository(String dbType) {
+        this.dbType = dbType;
+    }
 
     private Map<String, Schema> schemas = new LinkedHashMap<String, Schema>();
 
@@ -136,6 +151,10 @@ public class SchemaRepository {
         return getDefaultSchema().findFunction(functionName);
     }
 
+    public void acceptDDL(String ddl) {
+        acceptDDL(ddl, dbType);
+    }
+
     public void acceptDDL(String ddl, String dbType) {
         getDefaultSchema().acceptDDL(ddl, dbType);
     }
@@ -183,4 +202,53 @@ public class SchemaRepository {
     public int getViewCount() {
         return getDefaultSchema().getViewCount();
     }
+
+    public String console(String input) {
+        try {
+            StringBuffer buf = new StringBuffer();
+
+            List<SQLStatement> stmtList = SQLUtils.parseStatements(input, dbType);
+
+            for (SQLStatement stmt : stmtList) {
+                if (stmt instanceof MySqlShowColumnsStatement) {
+                    MySqlShowColumnsStatement showColumns = ((MySqlShowColumnsStatement) stmt);
+                    SQLName table = showColumns.getTable();
+                    SchemaObject schemaObject = findSchemaObject(table);
+                    MySqlCreateTableStatement createTableStmt = (MySqlCreateTableStatement) schemaObject.getStatement();
+                    createTableStmt.showCoumns(buf);
+                } else if (stmt instanceof MySqlShowCreateTableStatement) {
+                    MySqlShowCreateTableStatement showCreateTableStmt = (MySqlShowCreateTableStatement) stmt;
+                    SQLName table = showCreateTableStmt.getName();
+                    SchemaObject schemaObject = findSchemaObject(table);
+                    MySqlCreateTableStatement createTableStmt = (MySqlCreateTableStatement) schemaObject.getStatement();
+                    createTableStmt.output(buf);
+                }
+            }
+
+            return buf.toString();
+        } catch (IOException ex) {
+            throw new DruidRuntimeException("exeucte command error.", ex);
+        }
+    }
+
+    private SchemaObject findSchemaObject(SQLName name) {
+        if (name instanceof SQLIdentifierExpr) {
+            return findTable(((SQLIdentifierExpr) name).getName());
+        }
+
+        if (name instanceof SQLPropertyExpr) {
+            SQLPropertyExpr propertyExpr = (SQLPropertyExpr) name;
+            String schema = propertyExpr.getOwnernName();
+            String table = propertyExpr.getName();
+
+            Schema schemaObj = findSchema(schema);
+            if (schemaObj == null) {
+                return null;
+            }
+
+            return schemaObj.findTable(table);
+        }
+
+        return null;
+    }
 }

src/main/java/com/alibaba/druid/util/JdbcUtils.java

@@ -767,6 +767,18 @@ public final class JdbcUtils implements JdbcConstants {
         }
     }
 
+    public static List<String> showTables(Connection conn, String dbType) throws SQLException {
+        if (JdbcConstants.MYSQL.equals(dbType)) {
+            return MySqlUtils.showTables(conn);
+        }
+
+        if (JdbcConstants.ORACLE.equals(dbType)) {
+            return OracleUtils.showTables(conn);
+        }
+
+        throw new SQLException("show tables dbType not support for " + dbType);
+    }
+
     public static String getCreateTableScript(Connection conn, String dbType) throws SQLException {
         return getCreateTableScript(conn, dbType, true, true);
     }