support sql ast object toString

src/main/java/com/alibaba/druid/sql/ast/SQLStatementImpl.java

@@ -20,12 +20,26 @@ import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 
 public abstract class SQLStatementImpl extends SQLObjectImpl implements SQLStatement {
 
+    private String dbType;
+
     public SQLStatementImpl(){
 
     }
+    
+    public SQLStatementImpl(String dbType){
+        this.dbType = dbType;
+    }
+    
+    public String getDbType() {
+        return dbType;
+    }
+
+    public void setDbType(String dbType) {
+        this.dbType = dbType;
+    }
 
     public String toString() {
-        return SQLUtils.toSQLString(this);
+        return SQLUtils.toSQLString(this, dbType);
     }
 
     @Override

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

@@ -26,6 +26,14 @@ public class SQLAlterTableStatement extends SQLStatementImpl implements SQLDDLSt
 
     private SQLExprTableSource      tableSource;
     private List<SQLAlterTableItem> items = new ArrayList<SQLAlterTableItem>();
+    
+    public SQLAlterTableStatement() {
+        
+    }
+    
+    public SQLAlterTableStatement(String dbType) {
+        super (dbType);
+    }
 
     public List<SQLAlterTableItem> getItems() {
         return items;

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

@@ -33,6 +33,14 @@ public class SQLCallStatement extends SQLStatementImpl {
     private SQLName             procedureName;
 
     private final List<SQLExpr> parameters = new ArrayList<SQLExpr>();
+    
+    public SQLCallStatement() {
+        
+    }
+    
+    public SQLCallStatement(String dbType) {
+        super (dbType);
+    }
 
     public SQLVariantRefExpr getOutParameter() {
         return outParameter;

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

@@ -33,6 +33,10 @@ public class SQLCreateDatabaseStatement extends SQLStatementImpl {
 
     public SQLCreateDatabaseStatement(){
     }
+    
+    public SQLCreateDatabaseStatement(String dbType){
+        super (dbType);
+    }
 
     @Override
     protected void accept0(SQLASTVisitor visitor) {

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

@@ -35,6 +35,10 @@ public class SQLCreateIndexStatement extends SQLStatementImpl implements SQLDDLS
     public SQLCreateIndexStatement(){
 
     }
+    
+    public SQLCreateIndexStatement(String dbType){
+        super (dbType);
+    }
 
     public SQLTableSource getTable() {
         return table;

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

@@ -33,6 +33,10 @@ public class SQLCreateTableStatement extends SQLStatementImpl implements SQLDDLS
     public SQLCreateTableStatement(){
 
     }
+    
+    public SQLCreateTableStatement(String dbType){
+        super (dbType);
+    }
 
     public SQLName getName() {
         if (tableSource == null) {

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

@@ -37,6 +37,14 @@ public class SQLCreateTriggerStatement extends SQLStatementImpl {
     private boolean                  forEachRow    = false;
 
     private SQLStatement             body;
+    
+    public SQLCreateTriggerStatement() {
+        
+    }
+    
+    public SQLCreateTriggerStatement(String dbType) {
+        super (dbType);
+    }
 
     protected void accept0(SQLASTVisitor visitor) {
         if (visitor.visit(this)) {

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

@@ -36,6 +36,10 @@ public class SQLCreateViewStatement extends SQLStatementImpl implements SQLDDLSt
     public SQLCreateViewStatement(){
 
     }
+    
+    public SQLCreateViewStatement(String dbType){
+        super (dbType);
+    }
 
     public boolean isOrReplace() {
         return orReplace;

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

@@ -29,6 +29,10 @@ public class SQLDeleteStatement extends SQLStatementImpl {
     public SQLDeleteStatement(){
 
     }
+    
+    public SQLDeleteStatement(String dbType){
+        super (dbType);
+    }
 
     public SQLTableSource getTableSource() {
         return tableSource;

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

@@ -23,6 +23,14 @@ public class SQLDropDatabaseStatement extends SQLStatementImpl implements SQLDDL
 
     private SQLExpr database;
     private boolean ifExists;
+    
+    public SQLDropDatabaseStatement() {
+        
+    }
+    
+    public SQLDropDatabaseStatement(String dbType) {
+        super (dbType);
+    }
 
     @Override
     protected void accept0(SQLASTVisitor visitor) {

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

@@ -23,6 +23,14 @@ public class SQLDropFunctionStatement extends SQLStatementImpl implements SQLDDL
 
     private SQLName name;
     private boolean ifExists;
+    
+    public SQLDropFunctionStatement() {
+        
+    }
+    
+    public SQLDropFunctionStatement(String dbType) {
+        super (dbType);
+    }
 
     @Override
     protected void accept0(SQLASTVisitor visitor) {

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

@@ -23,6 +23,14 @@ public class SQLDropIndexStatement extends SQLStatementImpl implements SQLDDLSta
 
     private SQLExpr            indexName;
     private SQLExprTableSource tableName;
+    
+    public SQLDropIndexStatement() {
+        
+    }
+    
+    public SQLDropIndexStatement(String dbType) {
+        super (dbType);
+    }
 
     public SQLExpr getIndexName() {
         return indexName;

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

@@ -23,6 +23,14 @@ public class SQLDropProcedureStatement extends SQLStatementImpl implements SQLDD
 
     private SQLName name;
     private boolean ifExists;
+    
+    public SQLDropProcedureStatement() {
+        
+    }
+    
+    public SQLDropProcedureStatement(String dbType) {
+        super (dbType);
+    }
 
     @Override
     protected void accept0(SQLASTVisitor visitor) {

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

@@ -22,6 +22,14 @@ import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 public class SQLDropSequenceStatement extends SQLStatementImpl implements SQLDDLStatement {
 
     private SQLName name;
+    
+    public SQLDropSequenceStatement() {
+        
+    }
+    
+    public SQLDropSequenceStatement(String dbType) {
+        super (dbType);
+    }
 
     @Override
     protected void accept0(SQLASTVisitor visitor) {

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

@@ -23,6 +23,14 @@ public class SQLDropTableSpaceStatement extends SQLStatementImpl implements SQLD
 
     private SQLName name;
     private boolean ifExists;
+    
+    public SQLDropTableSpaceStatement() {
+        
+    }
+    
+    public SQLDropTableSpaceStatement(String dbType) {
+        super (dbType);
+    }
 
     @Override
     protected void accept0(SQLASTVisitor visitor) {

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

@@ -36,12 +36,25 @@ public class SQLDropTableStatement extends SQLStatementImpl implements SQLDDLSta
     public SQLDropTableStatement(){
 
     }
-
-    public SQLDropTableStatement(SQLName name){
-        this(new SQLExprTableSource(name));
+    
+    public SQLDropTableStatement(String dbType){
+        super (dbType);
     }
 
+    public SQLDropTableStatement(SQLName name, String dbType){
+        this(new SQLExprTableSource(name), dbType);
+    }
+    
+    public SQLDropTableStatement(SQLName name){
+        this (name, null);
+    }
+    
     public SQLDropTableStatement(SQLExprTableSource tableSource){
+        this (tableSource, null);
+    }
+
+    public SQLDropTableStatement(SQLExprTableSource tableSource, String dbType){
+        this (dbType);
         this.tableSources.add(tableSource);
     }
 

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

@@ -22,6 +22,14 @@ import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 public class SQLDropTriggerStatement extends SQLStatementImpl implements SQLDDLStatement {
 
     private SQLName name;
+    
+    public SQLDropTriggerStatement() {
+        
+    }
+    
+    public SQLDropTriggerStatement(String dbType) {
+        super (dbType);
+    }
 
     public SQLName getName() {
         return name;

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

@@ -25,6 +25,14 @@ import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 public class SQLDropUserStatement extends SQLStatementImpl implements SQLDDLStatement {
 
     private List<SQLExpr> users = new ArrayList<SQLExpr>(2);
+    
+    public SQLDropUserStatement() {
+        
+    }
+    
+    public SQLDropUserStatement(String dbType) {
+        super (dbType);
+    }
 
     public List<SQLExpr> getUsers() {
         return users;

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

@@ -33,6 +33,10 @@ public class SQLDropViewStatement extends SQLStatementImpl implements SQLDDLStat
     public SQLDropViewStatement(){
 
     }
+    
+    public SQLDropViewStatement(String dbType){
+        super (dbType);
+    }
 
     public SQLDropViewStatement(SQLName name){
         this(new SQLExprTableSource(name));

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

@@ -27,6 +27,14 @@ public class SQLExplainStatement extends SQLStatementImpl {
     protected SQLStatement       statement;
 
     private List<SQLCommentHint> hints;
+    
+    public SQLExplainStatement() {
+        
+    }
+    
+    public SQLExplainStatement(String dbType) {
+        super (dbType);
+    }
 
     public SQLStatement getStatement() {
         return statement;

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

@@ -28,6 +28,14 @@ public class SQLGrantStatement extends SQLStatementImpl {
 
     private SQLExpr             on;
     private SQLExpr             to;
+    
+    public SQLGrantStatement() {
+        
+    }
+    
+    public SQLGrantStatement(String dbType) {
+        super (dbType);
+    }
 
     // mysql
     private ObjectType          objectType;

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

@@ -22,6 +22,14 @@ import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 public class SQLReleaseSavePointStatement extends SQLStatementImpl {
 
     private SQLExpr name;
+    
+    public SQLReleaseSavePointStatement() {
+        
+    }
+    
+    public SQLReleaseSavePointStatement(String dbType) {
+        super (dbType);
+    }
 
     public SQLExpr getName() {
         return name;

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

@@ -22,6 +22,14 @@ import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 public class SQLRollbackStatement extends SQLStatementImpl {
 
     private SQLName to;
+    
+    public SQLRollbackStatement() {
+        
+    }
+    
+    public SQLRollbackStatement(String dbType) {
+        super (dbType);
+    }
 
     @Override
     protected void accept0(SQLASTVisitor visitor) {

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

@@ -22,6 +22,14 @@ import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 public class SQLSavePointStatement extends SQLStatementImpl {
 
     private SQLExpr name;
+    
+    public SQLSavePointStatement() {
+        
+    }
+    
+    public SQLSavePointStatement(String dbType) {
+        super (dbType);
+    }
 
     public SQLExpr getName() {
         return name;

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

@@ -26,10 +26,19 @@ public class SQLSelectStatement extends SQLStatementImpl {
 
     }
 
+    public SQLSelectStatement(String dbType){
+        super (dbType);
+    }
+
     public SQLSelectStatement(SQLSelect select){
         this.setSelect(select);
     }
 
+    public SQLSelectStatement(SQLSelect select, String dbType){
+        this(dbType);
+        this.setSelect(select);
+    }
+
     public SQLSelect getSelect() {
         return this.select;
     }

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

@@ -31,8 +31,17 @@ public class SQLSetStatement extends SQLStatementImpl {
 
     public SQLSetStatement(){
     }
-
+    
+    public SQLSetStatement(String dbType){
+        super (dbType);
+    }
+    
     public SQLSetStatement(SQLExpr target, SQLExpr value){
+        this(target, value, null);
+    }
+
+    public SQLSetStatement(SQLExpr target, SQLExpr value, String dbType){
+        super (dbType);
         this.items.add(new SQLAssignItem(target, value));
     }
 

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

@@ -31,6 +31,14 @@ public class SQLTruncateStatement extends SQLStatementImpl {
     private boolean                    only;
     private Boolean                    restartIdentity;
     private Boolean                    cascade;
+    
+    public SQLTruncateStatement() {
+        
+    }
+    
+    public SQLTruncateStatement(String dbType) {
+        super (dbType);
+    }
 
     public List<SQLExprTableSource> getTableSources() {
         return tableSources;

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

@@ -33,6 +33,10 @@ public class SQLUpdateStatement extends SQLStatementImpl {
     public SQLUpdateStatement(){
 
     }
+    
+    public SQLUpdateStatement(String dbType){
+        super (dbType);
+    }
 
     public SQLTableSource getTableSource() {
         return tableSource;

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

@@ -23,6 +23,14 @@ import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 public class SQLUseStatement extends SQLStatementImpl implements SQLStatement {
 
     private SQLName database;
+    
+    public SQLUseStatement() {
+        
+    }
+    
+    public SQLUseStatement(String dbType) {
+        super (dbType);
+    }
 
     public SQLName getDatabase() {
         return database;

src/main/java/com/alibaba/druid/sql/dialect/db2/ast/DB2StatementImpl.java

@@ -18,8 +18,14 @@ package com.alibaba.druid.sql.dialect.db2.ast;
 import com.alibaba.druid.sql.ast.SQLStatementImpl;
 import com.alibaba.druid.sql.dialect.db2.visitor.DB2ASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public abstract class DB2StatementImpl extends SQLStatementImpl implements DB2Object {
+
+    public DB2StatementImpl() {
+        super(JdbcConstants.DB2);
+    }
+
     @Override
     protected void accept0(SQLASTVisitor visitor) {
         if (visitor instanceof DB2ASTVisitor) {

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

@@ -18,10 +18,15 @@ package com.alibaba.druid.sql.dialect.mysql.ast.statement;
 import com.alibaba.druid.sql.ast.statement.SQLAlterTableStatement;
 import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class MySqlAlterTableStatement extends SQLAlterTableStatement {
 
     private boolean ignore = false;
+    
+    public MySqlAlterTableStatement() {
+        super (JdbcConstants.MYSQL);
+    }
 
     @Override
     protected void accept0(SQLASTVisitor visitor) {

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

@@ -18,10 +18,15 @@ package com.alibaba.druid.sql.dialect.mysql.ast.statement;
 import com.alibaba.druid.sql.ast.statement.SQLCreateIndexStatement;
 import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class MySqlCreateIndexStatement extends SQLCreateIndexStatement implements MySqlStatement {
 
     private String using;
+    
+    public MySqlCreateIndexStatement() {
+        super (JdbcConstants.MYSQL);
+    }
 
     public String getUsing() {
         return using;

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

@@ -31,6 +31,7 @@ import com.alibaba.druid.sql.ast.statement.SQLSelect;
 import com.alibaba.druid.sql.dialect.mysql.ast.MySqlObjectImpl;
 import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class MySqlCreateTableStatement extends SQLCreateTableStatement implements MySqlStatement {
 
@@ -47,7 +48,7 @@ public class MySqlCreateTableStatement extends SQLCreateTableStatement implement
     private SQLExprTableSource     like;
 
     public MySqlCreateTableStatement(){
-
+        super (JdbcConstants.MYSQL);
     }
 
     public SQLExprTableSource getLike() {

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

@@ -22,6 +22,7 @@ import com.alibaba.druid.sql.dialect.mysql.ast.statement.MySqlSelectQueryBlock.L
 import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlASTVisitor;
 import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlOutputVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class MySqlDeleteStatement extends SQLDeleteStatement {
 
@@ -33,6 +34,10 @@ public class MySqlDeleteStatement extends SQLDeleteStatement {
     private SQLTableSource using;
     private SQLOrderBy     orderBy;
     private Limit          limit;
+    
+    public MySqlDeleteStatement() {
+        super (JdbcConstants.MYSQL);
+    }
 
     public boolean isLowPriority() {
         return lowPriority;

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

@@ -19,6 +19,7 @@ import com.alibaba.druid.sql.ast.SQLExpr;
 import com.alibaba.druid.sql.ast.statement.SQLRollbackStatement;
 import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class MySqlRollbackStatement extends SQLRollbackStatement implements MySqlStatement {
 
@@ -28,7 +29,7 @@ public class MySqlRollbackStatement extends SQLRollbackStatement implements MySq
     private SQLExpr force;
 
     public MySqlRollbackStatement(){
-
+        super (JdbcConstants.MYSQL);
     }
 
     public Boolean getChain() {

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

@@ -18,9 +18,14 @@ package com.alibaba.druid.sql.dialect.mysql.ast.statement;
 import com.alibaba.druid.sql.ast.SQLStatementImpl;
 import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public abstract class MySqlStatementImpl extends SQLStatementImpl implements MySqlStatement {
 
+    public MySqlStatementImpl() {
+        super(JdbcConstants.MYSQL);
+    }
+
     @Override
     protected void accept0(SQLASTVisitor visitor) {
         if (visitor instanceof MySqlASTVisitor) {

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

@@ -20,6 +20,7 @@ import com.alibaba.druid.sql.ast.statement.SQLUpdateStatement;
 import com.alibaba.druid.sql.dialect.mysql.ast.statement.MySqlSelectQueryBlock.Limit;
 import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class MySqlUpdateStatement extends SQLUpdateStatement implements MySqlStatement {
 
@@ -28,6 +29,10 @@ public class MySqlUpdateStatement extends SQLUpdateStatement implements MySqlSta
 
     private boolean    lowPriority = false;
     private boolean    ignore      = false;
+    
+    public MySqlUpdateStatement() {
+        super (JdbcConstants.MYSQL);
+    }
 
     public Limit getLimit() {
         return limit;

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

@@ -147,6 +147,7 @@ import com.alibaba.druid.sql.parser.ParserException;
 import com.alibaba.druid.sql.parser.SQLSelectParser;
 import com.alibaba.druid.sql.parser.SQLStatementParser;
 import com.alibaba.druid.sql.parser.Token;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class MySqlStatementParser extends SQLStatementParser {
 
@@ -191,7 +192,7 @@ public class MySqlStatementParser extends SQLStatementParser {
 
     public SQLSelectStatement parseSelect() {
         MySqlSelectParser selectParser = new MySqlSelectParser(this.exprParser);
-        return new SQLSelectStatement(selectParser.select());
+        return new SQLSelectStatement(selectParser.select(), JdbcConstants.MYSQL);
     }
 
     public SQLUpdateStatement parseUpdateStatement() {
@@ -2131,7 +2132,7 @@ public class MySqlStatementParser extends SQLStatementParser {
             }
             return stmt;
         } else {
-            SQLSetStatement stmt = new SQLSetStatement();
+            SQLSetStatement stmt = new SQLSetStatement(getDbType());
 
             parseAssignItems(stmt.getItems(), stmt);
 
@@ -2536,7 +2537,7 @@ public class MySqlStatementParser extends SQLStatementParser {
 
         accept(Token.DATABASE);
 
-        SQLCreateDatabaseStatement stmt = new SQLCreateDatabaseStatement();
+        SQLCreateDatabaseStatement stmt = new SQLCreateDatabaseStatement(JdbcConstants.MYSQL);
         stmt.setName(this.exprParser.name());
 
         if (lexer.token() == Token.DEFAULT) {

src/main/java/com/alibaba/druid/sql/dialect/odps/ast/OdpsCreateTableStatement.java

@@ -25,6 +25,7 @@ import com.alibaba.druid.sql.ast.statement.SQLCreateTableStatement;
 import com.alibaba.druid.sql.ast.statement.SQLExprTableSource;
 import com.alibaba.druid.sql.dialect.odps.visitor.OdpsASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class OdpsCreateTableStatement extends SQLCreateTableStatement {
 
@@ -35,6 +36,10 @@ public class OdpsCreateTableStatement extends SQLCreateTableStatement {
     protected List<SQLColumnDefinition> partitionColumns = new ArrayList<SQLColumnDefinition>(2);
 
     protected SQLExpr                   lifecycle;
+    
+    public OdpsCreateTableStatement() {
+        super (JdbcConstants.ODPS);
+    }
 
     public SQLExprTableSource getLike() {
         return like;

src/main/java/com/alibaba/druid/sql/dialect/odps/ast/OdpsInsertStatement.java

@@ -23,12 +23,17 @@ import com.alibaba.druid.sql.ast.SQLStatementImpl;
 import com.alibaba.druid.sql.ast.statement.SQLSubqueryTableSource;
 import com.alibaba.druid.sql.dialect.odps.visitor.OdpsASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class OdpsInsertStatement extends SQLStatementImpl implements SQLStatement {
 
     private SQLSubqueryTableSource from;
 
     private List<OdpsInsert>       items = new ArrayList<OdpsInsert>();
+    
+    public OdpsInsertStatement() {
+        super (JdbcConstants.ODPS);
+    }
 
     public void setFrom(SQLSubqueryTableSource from) {
         this.from = from;

src/main/java/com/alibaba/druid/sql/dialect/odps/ast/OdpsShowPartitionsStmt.java

@@ -5,10 +5,15 @@ import com.alibaba.druid.sql.ast.SQLStatementImpl;
 import com.alibaba.druid.sql.ast.statement.SQLExprTableSource;
 import com.alibaba.druid.sql.dialect.odps.visitor.OdpsASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class OdpsShowPartitionsStmt extends SQLStatementImpl implements SQLStatement {
 
     private SQLExprTableSource tableSource;
+    
+    public OdpsShowPartitionsStmt() {
+        super (JdbcConstants.ODPS);
+    }
 
     public SQLExprTableSource getTableSource() {
         return tableSource;

src/main/java/com/alibaba/druid/sql/dialect/odps/ast/OdpsShowStatisticStmt.java

@@ -5,10 +5,15 @@ import com.alibaba.druid.sql.ast.SQLStatementImpl;
 import com.alibaba.druid.sql.ast.statement.SQLExprTableSource;
 import com.alibaba.druid.sql.dialect.odps.visitor.OdpsASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class OdpsShowStatisticStmt extends SQLStatementImpl implements SQLStatement {
 
     private SQLExprTableSource tableSource;
+    
+    public OdpsShowStatisticStmt() {
+        super (JdbcConstants.ODPS);
+    }
 
     public SQLExprTableSource getTableSource() {
         return tableSource;

src/main/java/com/alibaba/druid/sql/dialect/oracle/ast/stmt/OracleAlterTableStatement.java

@@ -18,11 +18,16 @@ package com.alibaba.druid.sql.dialect.oracle.ast.stmt;
 import com.alibaba.druid.sql.ast.statement.SQLAlterTableStatement;
 import com.alibaba.druid.sql.dialect.oracle.visitor.OracleASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class OracleAlterTableStatement extends SQLAlterTableStatement implements OracleDDLStatement {
 
     private boolean updateGlobalIndexes     = false;
     private boolean invalidateGlobalIndexes = false;
+    
+    public OracleAlterTableStatement() {
+        super (JdbcConstants.ORACLE);
+    }
 
     protected void accept0(SQLASTVisitor visitor) {
         accept0((OracleASTVisitor) visitor);

src/main/java/com/alibaba/druid/sql/dialect/oracle/ast/stmt/OracleCreateIndexStatement.java

@@ -20,6 +20,7 @@ import com.alibaba.druid.sql.ast.SQLName;
 import com.alibaba.druid.sql.ast.statement.SQLCreateIndexStatement;
 import com.alibaba.druid.sql.dialect.oracle.visitor.OracleASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class OracleCreateIndexStatement extends SQLCreateIndexStatement implements OracleDDLStatement {
 
@@ -41,6 +42,10 @@ public class OracleCreateIndexStatement extends SQLCreateIndexStatement implemen
     private Boolean enable            = null;
 
     private boolean computeStatistics = false;
+    
+    public OracleCreateIndexStatement() {
+        super (JdbcConstants.ORACLE);
+    }
 
     public SQLName getTablespace() {
         return tablespace;

src/main/java/com/alibaba/druid/sql/dialect/oracle/ast/stmt/OracleCreateTableStatement.java

@@ -24,6 +24,7 @@ import com.alibaba.druid.sql.dialect.oracle.ast.clause.OracleLobStorageClause;
 import com.alibaba.druid.sql.dialect.oracle.ast.clause.OracleStorageClause;
 import com.alibaba.druid.sql.dialect.oracle.visitor.OracleASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class OracleCreateTableStatement extends SQLCreateTableStatement implements OracleDDLStatement {
 
@@ -58,6 +59,10 @@ public class OracleCreateTableStatement extends SQLCreateTableStatement implemen
     private SQLPartitioningClause   partitioning;
 
     private DeferredSegmentCreation deferredSegmentCreation;
+    
+    public OracleCreateTableStatement() {
+        super (JdbcConstants.ORACLE);
+    }
 
     public OracleLobStorageClause getLobStorage() {
         return lobStorage;

src/main/java/com/alibaba/druid/sql/dialect/oracle/ast/stmt/OracleDeleteStatement.java

@@ -23,6 +23,7 @@ import com.alibaba.druid.sql.ast.statement.SQLDeleteStatement;
 import com.alibaba.druid.sql.dialect.oracle.ast.clause.OracleReturningClause;
 import com.alibaba.druid.sql.dialect.oracle.visitor.OracleASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class OracleDeleteStatement extends SQLDeleteStatement {
 
@@ -32,7 +33,7 @@ public class OracleDeleteStatement extends SQLDeleteStatement {
     private OracleReturningClause returning = null;
 
     public OracleDeleteStatement(){
-
+        super (JdbcConstants.ORACLE);
     }
 
     public OracleReturningClause getReturning() {

src/main/java/com/alibaba/druid/sql/dialect/oracle/ast/stmt/OracleExplainStatement.java

@@ -21,11 +21,16 @@ import com.alibaba.druid.sql.ast.expr.SQLCharExpr;
 import com.alibaba.druid.sql.ast.statement.SQLExplainStatement;
 import com.alibaba.druid.sql.dialect.oracle.visitor.OracleASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class OracleExplainStatement extends SQLExplainStatement implements OracleStatement {
 
     private SQLCharExpr statementId;
     private SQLExpr     into;
+    
+    public OracleExplainStatement() {
+        super (JdbcConstants.ORACLE);
+    }
 
     @Override
     public void accept0(OracleASTVisitor visitor) {

src/main/java/com/alibaba/druid/sql/dialect/oracle/ast/stmt/OracleStatementImpl.java

@@ -19,8 +19,13 @@ import com.alibaba.druid.sql.SQLUtils;
 import com.alibaba.druid.sql.ast.SQLStatementImpl;
 import com.alibaba.druid.sql.dialect.oracle.visitor.OracleASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public abstract class OracleStatementImpl extends SQLStatementImpl implements OracleStatement {
+    
+    public OracleStatementImpl() {
+        super(JdbcConstants.ORACLE);
+    }
 
     protected void accept0(SQLASTVisitor visitor) {
         accept0((OracleASTVisitor) visitor);

src/main/java/com/alibaba/druid/sql/dialect/oracle/ast/stmt/OracleUpdateStatement.java

@@ -23,6 +23,7 @@ import com.alibaba.druid.sql.ast.SQLHint;
 import com.alibaba.druid.sql.ast.statement.SQLUpdateStatement;
 import com.alibaba.druid.sql.dialect.oracle.visitor.OracleASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class OracleUpdateStatement extends SQLUpdateStatement implements OracleStatement {
 
@@ -35,7 +36,7 @@ public class OracleUpdateStatement extends SQLUpdateStatement implements OracleS
     private List<SQLExpr>       returningInto = new ArrayList<SQLExpr>();
 
     public OracleUpdateStatement(){
-
+        super (JdbcConstants.ORACLE);
     }
 
     public List<SQLExpr> getReturning() {

src/main/java/com/alibaba/druid/sql/dialect/oracle/parser/OracleStatementParser.java

@@ -105,6 +105,7 @@ import com.alibaba.druid.sql.parser.Lexer;
 import com.alibaba.druid.sql.parser.ParserException;
 import com.alibaba.druid.sql.parser.SQLStatementParser;
 import com.alibaba.druid.sql.parser.Token;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class OracleStatementParser extends SQLStatementParser {
 
@@ -163,7 +164,8 @@ public class OracleStatementParser extends SQLStatementParser {
             }
 
             if (lexer.token() == (Token.SELECT)) {
-                statementList.add(new SQLSelectStatement(new OracleSelectParser(this.exprParser).select()));
+                SQLSelectStatement stmt = new SQLSelectStatement(new OracleSelectParser(this.exprParser).select(), JdbcConstants.ORACLE); 
+                statementList.add(stmt);
                 continue;
             }
 
@@ -238,7 +240,7 @@ public class OracleStatementParser extends SQLStatementParser {
                 if (variant instanceof SQLBinaryOpExpr) {
                     SQLBinaryOpExpr binaryOpExpr = (SQLBinaryOpExpr) variant;
                     if (binaryOpExpr.getOperator() == SQLBinaryOperator.Assignment) {
-                        SQLSetStatement stmt = new SQLSetStatement(binaryOpExpr.getLeft(), binaryOpExpr.getRight());
+                        SQLSetStatement stmt = new SQLSetStatement(binaryOpExpr.getLeft(), binaryOpExpr.getRight(), getDbType());
                         statementList.add(stmt);
                         continue;
                     }
@@ -246,7 +248,7 @@ public class OracleStatementParser extends SQLStatementParser {
                 accept(Token.COLONEQ);
                 SQLExpr value = this.exprParser.expr();
 
-                SQLSetStatement stmt = new SQLSetStatement(variant, value);
+                SQLSetStatement stmt = new SQLSetStatement(variant, value, getDbType());
                 statementList.add(stmt);
                 continue;
             }

src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/stmt/PGDeleteStatement.java

@@ -23,6 +23,7 @@ import com.alibaba.druid.sql.ast.statement.SQLDeleteStatement;
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGWithClause;
 import com.alibaba.druid.sql.dialect.postgresql.visitor.PGASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class PGDeleteStatement extends SQLDeleteStatement implements PGSQLStatement {
 
@@ -31,6 +32,10 @@ public class PGDeleteStatement extends SQLDeleteStatement implements PGSQLStatem
     private List<SQLName> using = new ArrayList<SQLName>(2);
     private boolean       returning;
     private String        alias;
+    
+    public PGDeleteStatement() {
+        super (JdbcConstants.POSTGRESQL);
+    }
 
     public boolean isReturning() {
         return returning;

src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/stmt/PGSelectStatement.java

@@ -20,16 +20,18 @@ import com.alibaba.druid.sql.ast.statement.SQLSelectStatement;
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGWithClause;
 import com.alibaba.druid.sql.dialect.postgresql.visitor.PGASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class PGSelectStatement extends SQLSelectStatement implements PGSQLStatement {
 
     private PGWithClause with;
 
     public PGSelectStatement(){
+        super(JdbcConstants.POSTGRESQL);
     }
 
     public PGSelectStatement(SQLSelect select){
-        super(select);
+        super(select, JdbcConstants.POSTGRESQL);
     }
 
     public PGWithClause getWith() {

src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/stmt/PGUpdateStatement.java

@@ -24,6 +24,7 @@ import com.alibaba.druid.sql.ast.statement.SQLUpdateStatement;
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGWithClause;
 import com.alibaba.druid.sql.dialect.postgresql.visitor.PGASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class PGUpdateStatement extends SQLUpdateStatement implements PGSQLStatement {
 
@@ -34,6 +35,10 @@ public class PGUpdateStatement extends SQLUpdateStatement implements PGSQLStatem
     private List<SQLExpr>  returning = new ArrayList<SQLExpr>(2);
 
     private SQLTableSource from;
+    
+    public PGUpdateStatement(){
+        super (JdbcConstants.POSTGRESQL);
+    }
 
     public SQLTableSource getFrom() {
         return from;

src/main/java/com/alibaba/druid/sql/dialect/sqlserver/ast/stmt/SQLServerUpdateStatement.java

@@ -22,12 +22,17 @@ import com.alibaba.druid.sql.dialect.sqlserver.ast.SQLServerStatement;
 import com.alibaba.druid.sql.dialect.sqlserver.ast.SQLServerTop;
 import com.alibaba.druid.sql.dialect.sqlserver.visitor.SQLServerASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.util.JdbcConstants;
 
 public class SQLServerUpdateStatement extends SQLUpdateStatement implements SQLServerStatement {
 
     private SQLServerTop    top;
     private SQLTableSource  from;
     private SQLServerOutput output;
+    
+    public SQLServerUpdateStatement(){
+        super (JdbcConstants.SQL_SERVER);
+    }
 
     public SQLServerTop getTop() {
         return top;

src/main/java/com/alibaba/druid/sql/dialect/sqlserver/parser/SQLServerStatementParser.java

@@ -355,7 +355,7 @@ public class SQLServerStatementParser extends SQLStatementParser {
         }
 
         if (lexer.token() == Token.VARIANT) {
-            SQLSetStatement stmt = new SQLSetStatement();
+            SQLSetStatement stmt = new SQLSetStatement(getDbType());
             parseAssignItems(stmt.getItems(), stmt);
             return stmt;
         } else {

src/main/java/com/alibaba/druid/sql/parser/SQLCreateTableParser.java

@@ -115,6 +115,6 @@ public class SQLCreateTableParser extends SQLDDLParser {
     }
 
     protected SQLCreateTableStatement newCreateStatement() {
-        return new SQLCreateTableStatement();
+        return new SQLCreateTableStatement(getDbType());
     }
 }

src/main/java/com/alibaba/druid/sql/parser/SQLExprParser.java

@@ -87,10 +87,18 @@ public class SQLExprParser extends SQLParser {
     public SQLExprParser(String sql){
         super(sql);
     }
+    
+    public SQLExprParser(String sql, String dbType){
+        super(sql, dbType);
+    }
 
     public SQLExprParser(Lexer lexer){
         super(lexer);
     }
+    
+    public SQLExprParser(Lexer lexer, String dbType){
+        super(lexer, dbType);
+    }
 
     public SQLExpr expr() {
         if (lexer.token() == Token.STAR) {

src/main/java/com/alibaba/druid/sql/parser/SQLParser.java

@@ -19,19 +19,34 @@ public class SQLParser {
 
     protected final Lexer lexer;
 
-    public SQLParser(String sql){
-        this(new Lexer(sql));
+    protected String      dbType;
+
+    public SQLParser(String sql, String dbType){
+        this(new Lexer(sql), dbType);
         this.lexer.nextToken();
     }
 
+    public SQLParser(String sql){
+        this(sql, null);
+    }
+
     public SQLParser(Lexer lexer){
+        this(lexer, null);
+    }
+
+    public SQLParser(Lexer lexer, String dbType){
         this.lexer = lexer;
+        this.dbType = dbType;
     }
 
     public final Lexer getLexer() {
         return lexer;
     }
 
+    public String getDbType() {
+        return dbType;
+    }
+
     protected boolean identifierEquals(String text) {
         return lexer.token() == Token.IDENTIFIER && lexer.stringVal().equalsIgnoreCase(text);
     }
@@ -143,7 +158,7 @@ public class SQLParser {
                     alias += ('.' + lexer.token().name());
                     lexer.nextToken();
                 }
-                
+
                 return alias;
             }
 
@@ -169,7 +184,7 @@ public class SQLParser {
         } else if (lexer.token() == Token.USER) {
             alias = lexer.stringVal();
             lexer.nextToken();
-        } 
+        }
 
         switch (lexer.token()) {
             case KEY:
@@ -184,7 +199,7 @@ public class SQLParser {
         return alias;
     }
 
-    protected void printError(Token token){
+    protected void printError(Token token) {
         String arround;
         if (lexer.mark >= 0 && (lexer.text.length() > lexer.mark + 30)) {
             if (lexer.mark - 5 > 0) {
@@ -202,7 +217,7 @@ public class SQLParser {
         } else {
             arround = lexer.text;
         }
-        
+
         // throw new
         // ParserException("syntax error, error arround:'"+arround+"',expect "
         // + token + ", actual " + lexer.token() + " "
@@ -210,7 +225,7 @@ public class SQLParser {
         throw new ParserException("syntax error, error in :'" + arround + "',expect " + token + ", actual "
                                   + lexer.token() + " " + lexer.stringVal());
     }
-    
+
     public void accept(Token token) {
         if (lexer.token() == token) {
             lexer.nextToken();
@@ -223,7 +238,7 @@ public class SQLParser {
     public void match(Token token) {
         if (lexer.token() != token) {
             throw new ParserException("syntax error, expect " + token + ", actual " + lexer.token() + " "
-                                        + lexer.stringVal());
+                                      + lexer.stringVal());
         }
     }
 

src/main/java/com/alibaba/druid/sql/parser/SQLStatementParser.java

@@ -90,11 +90,15 @@ public class SQLStatementParser extends SQLParser {
     protected int           parseValuesSize     = 3;
 
     public SQLStatementParser(String sql){
-        this(new SQLExprParser(sql));
+        this(sql, null);
+    }
+
+    public SQLStatementParser(String sql, String dbType){
+        this(new SQLExprParser(sql, dbType));
     }
 
     public SQLStatementParser(SQLExprParser exprParser){
-        super(exprParser.getLexer());
+        super(exprParser.getLexer(), exprParser.getDbType());
         this.exprParser = exprParser;
     }
 
@@ -315,7 +319,7 @@ public class SQLStatementParser extends SQLParser {
             lexer.nextToken();
         }
 
-        SQLRollbackStatement stmt = new SQLRollbackStatement();
+        SQLRollbackStatement stmt = new SQLRollbackStatement(getDbType());
 
         if (lexer.token() == Token.TO) {
             lexer.nextToken();
@@ -339,14 +343,14 @@ public class SQLStatementParser extends SQLParser {
 
     public SQLUseStatement parseUse() {
         accept(Token.USE);
-        SQLUseStatement stmt = new SQLUseStatement();
+        SQLUseStatement stmt = new SQLUseStatement(getDbType());
         stmt.setDatabase(this.exprParser.name());
         return stmt;
     }
 
     public SQLGrantStatement parseGrant() {
         accept(Token.GRANT);
-        SQLGrantStatement stmt = new SQLGrantStatement();
+        SQLGrantStatement stmt = new SQLGrantStatement(getDbType());
 
         for (;;) {
             String privilege = null;
@@ -619,7 +623,7 @@ public class SQLStatementParser extends SQLParser {
             acceptIdentifier("OPTION");
             stmt.setAdminOption(true);
         }
-        
+
         if (lexer.token() == Token.IDENTIFIED) {
             lexer.nextToken();
             accept(Token.BY);
@@ -631,7 +635,7 @@ public class SQLStatementParser extends SQLParser {
 
     public SQLStatement parseSavePoint() {
         acceptIdentifier("SAVEPOINT");
-        SQLSavePointStatement stmt = new SQLSavePointStatement();
+        SQLSavePointStatement stmt = new SQLSavePointStatement(getDbType());
         stmt.setName(this.exprParser.name());
         return stmt;
     }
@@ -639,7 +643,7 @@ public class SQLStatementParser extends SQLParser {
     public SQLStatement parseReleaseSavePoint() {
         acceptIdentifier("RELEASE");
         acceptIdentifier("SAVEPOINT");
-        SQLReleaseSavePointStatement stmt = new SQLReleaseSavePointStatement();
+        SQLReleaseSavePointStatement stmt = new SQLReleaseSavePointStatement(getDbType());
         stmt.setName(this.exprParser.name());
         return stmt;
     }
@@ -752,7 +756,7 @@ public class SQLStatementParser extends SQLParser {
             accept(Token.DROP);
         }
 
-        SQLDropTableStatement stmt = new SQLDropTableStatement();
+        SQLDropTableStatement stmt = new SQLDropTableStatement(getDbType());
 
         if (identifierEquals("TEMPORARY")) {
             lexer.nextToken();
@@ -816,7 +820,7 @@ public class SQLStatementParser extends SQLParser {
 
         SQLName name = this.exprParser.name();
 
-        SQLDropSequenceStatement stmt = new SQLDropSequenceStatement();
+        SQLDropSequenceStatement stmt = new SQLDropSequenceStatement(getDbType());
         stmt.setName(name);
         return stmt;
     }
@@ -830,7 +834,7 @@ public class SQLStatementParser extends SQLParser {
 
         SQLName name = this.exprParser.name();
 
-        SQLDropTriggerStatement stmt = new SQLDropTriggerStatement();
+        SQLDropTriggerStatement stmt = new SQLDropTriggerStatement(getDbType());
         stmt.setName(name);
         return stmt;
     }
@@ -840,7 +844,7 @@ public class SQLStatementParser extends SQLParser {
             accept(Token.DROP);
         }
 
-        SQLDropViewStatement stmt = new SQLDropViewStatement();
+        SQLDropViewStatement stmt = new SQLDropViewStatement(getDbType());
 
         accept(Token.VIEW);
 
@@ -881,7 +885,7 @@ public class SQLStatementParser extends SQLParser {
             accept(Token.DROP);
         }
 
-        SQLDropDatabaseStatement stmt = new SQLDropDatabaseStatement();
+        SQLDropDatabaseStatement stmt = new SQLDropDatabaseStatement(getDbType());
 
         accept(Token.DATABASE);
 
@@ -896,67 +900,67 @@ public class SQLStatementParser extends SQLParser {
 
         return stmt;
     }
-    
+
     protected SQLDropFunctionStatement parseDropFunction(boolean acceptDrop) {
         if (acceptDrop) {
             accept(Token.DROP);
         }
-        
-        SQLDropFunctionStatement stmt = new SQLDropFunctionStatement();
-        
+
+        SQLDropFunctionStatement stmt = new SQLDropFunctionStatement(getDbType());
+
         accept(Token.FUNCTION);
-        
+
         if (lexer.token() == Token.IF) {
             lexer.nextToken();
             accept(Token.EXISTS);
             stmt.setIfExists(true);
         }
-        
+
         SQLName name = this.exprParser.name();
         stmt.setName(name);
-        
+
         return stmt;
     }
-    
+
     protected SQLDropTableSpaceStatement parseDropTablespace(boolean acceptDrop) {
         if (acceptDrop) {
             accept(Token.DROP);
         }
-        
-        SQLDropTableSpaceStatement stmt = new SQLDropTableSpaceStatement();
-        
+
+        SQLDropTableSpaceStatement stmt = new SQLDropTableSpaceStatement(getDbType());
+
         accept(Token.TABLESPACE);
-        
+
         if (lexer.token() == Token.IF) {
             lexer.nextToken();
             accept(Token.EXISTS);
             stmt.setIfExists(true);
         }
-        
+
         SQLName name = this.exprParser.name();
         stmt.setName(name);
-        
+
         return stmt;
     }
-    
+
     protected SQLDropProcedureStatement parseDropProcedure(boolean acceptDrop) {
         if (acceptDrop) {
             accept(Token.DROP);
         }
-        
-        SQLDropProcedureStatement stmt = new SQLDropProcedureStatement();
-        
+
+        SQLDropProcedureStatement stmt = new SQLDropProcedureStatement(getDbType());
+
         accept(Token.PROCEDURE);
-        
+
         if (lexer.token() == Token.IF) {
             lexer.nextToken();
             accept(Token.EXISTS);
             stmt.setIfExists(true);
         }
-        
+
         SQLName name = this.exprParser.name();
         stmt.setName(name);
-        
+
         return stmt;
     }
 
@@ -965,7 +969,7 @@ public class SQLStatementParser extends SQLParser {
         if (lexer.token() == Token.TABLE) {
             lexer.nextToken();
         }
-        SQLTruncateStatement stmt = new SQLTruncateStatement();
+        SQLTruncateStatement stmt = new SQLTruncateStatement(getDbType());
 
         if (lexer.token() == Token.ONLY) {
             lexer.nextToken();
@@ -1090,7 +1094,7 @@ public class SQLStatementParser extends SQLParser {
     public SQLDropUserStatement parseDropUser() {
         accept(Token.USER);
 
-        SQLDropUserStatement stmt = new SQLDropUserStatement();
+        SQLDropUserStatement stmt = new SQLDropUserStatement(getDbType());
         for (;;) {
             SQLExpr expr = this.exprParser.expr();
             stmt.getUsers().add(expr);
@@ -1106,7 +1110,7 @@ public class SQLStatementParser extends SQLParser {
 
     public SQLStatement parseDropIndex() {
         accept(Token.INDEX);
-        SQLDropIndexStatement stmt = new SQLDropIndexStatement();
+        SQLDropIndexStatement stmt = new SQLDropIndexStatement(getDbType());
         stmt.setIndexName(this.exprParser.name());
 
         if (lexer.token() == Token.ON) {
@@ -1123,9 +1127,9 @@ public class SQLStatementParser extends SQLParser {
             lexer.nextToken();
             brace = true;
         }
-        
-        SQLCallStatement stmt = new SQLCallStatement();
-        
+
+        SQLCallStatement stmt = new SQLCallStatement(getDbType());
+
         if (lexer.token() == Token.QUES) {
             lexer.nextToken();
             accept(Token.EQ);
@@ -1134,7 +1138,6 @@ public class SQLStatementParser extends SQLParser {
 
         acceptIdentifier("CALL");
 
-       
         stmt.setProcedureName(exprParser.name());
 
         if (lexer.token() == Token.LPAREN) {
@@ -1153,7 +1156,7 @@ public class SQLStatementParser extends SQLParser {
 
     public SQLStatement parseSet() {
         accept(Token.SET);
-        SQLSetStatement stmt = new SQLSetStatement();
+        SQLSetStatement stmt = new SQLSetStatement(getDbType());
 
         parseAssignItems(stmt.getItems(), stmt);
 
@@ -1231,7 +1234,7 @@ public class SQLStatementParser extends SQLParser {
     public SQLStatement parseCreateTrigger() {
         accept(Token.TRIGGER);
 
-        SQLCreateTriggerStatement stmt = new SQLCreateTriggerStatement();
+        SQLCreateTriggerStatement stmt = new SQLCreateTriggerStatement(getDbType());
         stmt.setName(this.exprParser.name());
 
         if (identifierEquals("BEFORE")) {
@@ -1293,7 +1296,7 @@ public class SQLStatementParser extends SQLParser {
 
         accept(Token.DATABASE);
 
-        SQLCreateDatabaseStatement stmt = new SQLCreateDatabaseStatement();
+        SQLCreateDatabaseStatement stmt = new SQLCreateDatabaseStatement(getDbType());
         stmt.setName(this.exprParser.name());
         return stmt;
     }
@@ -1311,7 +1314,7 @@ public class SQLStatementParser extends SQLParser {
             accept(Token.CREATE);
         }
 
-        SQLCreateIndexStatement stmt = new SQLCreateIndexStatement();
+        SQLCreateIndexStatement stmt = new SQLCreateIndexStatement(getDbType());
         if (lexer.token() == Token.UNIQUE) {
             lexer.nextToken();
             if (identifierEquals("CLUSTERED")) {
@@ -1415,11 +1418,11 @@ public class SQLStatementParser extends SQLParser {
     }
 
     protected SQLUpdateStatement createUpdateStatement() {
-        return new SQLUpdateStatement();
+        return new SQLUpdateStatement(getDbType());
     }
 
     public SQLDeleteStatement parseDeleteStatement() {
-        SQLDeleteStatement deleteStatement = new SQLDeleteStatement();
+        SQLDeleteStatement deleteStatement = new SQLDeleteStatement(getDbType());
 
         if (lexer.token() == Token.DELETE) {
             lexer.nextToken();
@@ -1452,7 +1455,7 @@ public class SQLStatementParser extends SQLParser {
     }
 
     public SQLCreateViewStatement parseCreateView() {
-        SQLCreateViewStatement createView = new SQLCreateViewStatement();
+        SQLCreateViewStatement createView = new SQLCreateViewStatement(getDbType());
 
         if (lexer.token() == Token.CREATE) {
             lexer.nextToken();
@@ -1534,10 +1537,10 @@ public class SQLStatementParser extends SQLParser {
         if (lexer.token() == Token.FOR) {
             lexer.nextToken();
         }
-        
-        SQLExplainStatement explain = new SQLExplainStatement();
-        
-        if(lexer.token == Token.HINT) {
+
+        SQLExplainStatement explain = new SQLExplainStatement(getDbType());
+
+        if (lexer.token == Token.HINT) {
             explain.setHints(this.exprParser.parseHints());
         }
 
@@ -1579,7 +1582,6 @@ public class SQLStatementParser extends SQLParser {
         return item;
     }
 
-    
     public boolean isParseCompleteValues() {
         return parseCompleteValues;
     }

src/test/java/com/alibaba/druid/bvt/bug/Issue_685.java

@@ -0,0 +1,15 @@
+package com.alibaba.druid.bvt.bug;
+
+import junit.framework.TestCase;
+
+import com.alibaba.druid.sql.ast.SQLStatement;
+import com.alibaba.druid.sql.dialect.oracle.parser.OracleStatementParser;
+
+public class Issue_685 extends TestCase {
+
+    public void test_for_issue() throws Exception {
+        OracleStatementParser parser = new OracleStatementParser("select upper(*) from aa order by now()");
+        SQLStatement st = parser.parseStatement();
+        st.toString();
+    }
+}