improved sql parser.

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

@@ -25,7 +25,6 @@ import com.alibaba.druid.util.JdbcConstants;
 
 public class MySqlKey extends SQLUnique implements SQLUniqueConstraint, SQLTableConstraint {
 
-
     private String  indexType;
 
     private boolean hasConstaint;
@@ -66,4 +65,15 @@ public class MySqlKey extends SQLUnique implements SQLUniqueConstraint, SQLTable
         this.hasConstaint = hasConstaint;
     }
 
+    public void cloneTo(MySqlKey x) {
+        super.cloneTo(x);
+        x.indexType = indexType;
+        x.hasConstaint = hasConstaint;
+    }
+
+    public MySqlKey clone() {
+        MySqlKey x = new MySqlKey();
+        cloneTo(x);
+        return x;
+    }
 }

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

@@ -32,4 +32,10 @@ public class MySqlPrimaryKey extends MySqlKey implements SQLPrimaryKey {
         }
         visitor.endVisit(this);
     }
+
+    public MySqlPrimaryKey clone() {
+        MySqlPrimaryKey x = new MySqlPrimaryKey();
+        cloneTo(x);
+        return x;
+    }
 }

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

@@ -31,4 +31,10 @@ public class MySqlUnique extends MySqlKey {
         }
         visitor.endVisit(this);
     }
+
+    public MySqlUnique clone() {
+        MySqlUnique x = new MySqlUnique();
+        cloneTo(x);
+        return x;
+    }
 }

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

@@ -342,4 +342,38 @@ public class MySqlCreateTableStatement extends SQLCreateTableStatement implement
     public void output(StringBuffer buf) {
         this.accept(new MySqlOutputVisitor(buf));
     }
+
+    public void cloneTo(MySqlCreateTableStatement x) {
+        super.cloneTo(x);
+        for (Map.Entry<String, SQLObject> entry : tableOptions.entrySet()) {
+            SQLObject obj = entry.getValue().clone();
+            obj.setParent(x);
+            x.tableOptions.put(entry.getKey(), obj);
+        }
+        if (partitioning != null) {
+            x.setPartitioning(partitioning.clone());
+        }
+        for (SQLCommentHint hint : hints) {
+            SQLCommentHint h2 = hint.clone();
+            h2.setParent(x);
+            x.hints.add(h2);
+        }
+        for (SQLCommentHint hint : optionHints) {
+            SQLCommentHint h2 = hint.clone();
+            h2.setParent(x);
+            x.optionHints.add(h2);
+        }
+        if (like != null) {
+            x.setLike(like.clone());
+        }
+        if (tableGroup != null) {
+            x.setTableGroup(tableGroup.clone());
+        }
+    }
+
+    public MySqlCreateTableStatement clone() {
+        MySqlCreateTableStatement x = new MySqlCreateTableStatement();
+        cloneTo(x);
+        return x;
+    }
 }

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

@@ -59,4 +59,18 @@ public class MySqlPartitionByKey extends SQLPartitionBy implements MySqlObject {
         this.columns.add(column);
     }
 
+    public void cloneTo(MySqlPartitionByKey x) {
+        super.cloneTo(x);
+        for (SQLName column : columns) {
+            SQLName c2 = column.clone();
+            c2.setParent(x);
+            x.columns.add(c2);
+        }
+    }
+
+    public MySqlPartitionByKey clone() {
+        MySqlPartitionByKey x = new MySqlPartitionByKey();
+        cloneTo(x);
+        return x;
+    }
 }

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

@@ -57,4 +57,18 @@ public class MySqlSubPartitionByKey extends SQLSubPartitionBy implements MySqlOb
         this.columns.add(column);
     }
 
+    public void cloneTo(MySqlSubPartitionByKey x) {
+        super.cloneTo(x);
+        for (SQLName column : columns) {
+            SQLName c2 = column.clone();
+            c2.setParent(x);
+            x.columns.add(c2);
+        }
+    }
+
+    public MySqlSubPartitionByKey clone() {
+        MySqlSubPartitionByKey x = new MySqlSubPartitionByKey();
+        cloneTo(x);
+        return x;
+    }
 }

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

@@ -19,6 +19,7 @@ import java.util.ArrayList;
 import java.util.List;
 
 import com.alibaba.druid.sql.ast.SQLExpr;
+import com.alibaba.druid.sql.ast.SQLName;
 import com.alibaba.druid.sql.ast.SQLSubPartitionBy;
 import com.alibaba.druid.sql.ast.statement.SQLColumnDefinition;
 import com.alibaba.druid.sql.dialect.mysql.ast.MySqlObject;
@@ -72,4 +73,21 @@ public class MySqlSubPartitionByList extends SQLSubPartitionBy implements MySqlO
         this.columns.add(column);
     }
 
+    public void cloneTo(MySqlSubPartitionByList x) {
+        super.cloneTo(x);
+        if (expr != null) {
+            x.setExpr(expr.clone());
+        }
+        for (SQLColumnDefinition column : columns) {
+            SQLColumnDefinition c2 = column.clone();
+            c2.setParent(x);
+            x.columns.add(c2);
+        }
+    }
+
+    public MySqlSubPartitionByList clone() {
+        MySqlSubPartitionByList x = new MySqlSubPartitionByList();
+        cloneTo(x);
+        return x;
+    }
 }

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.SQLColumnDefinition;
 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;
@@ -69,4 +70,18 @@ public class MySqlTableIndex extends MySqlObjectImpl implements SQLTableElement
         }
         visitor.endVisit(this);
     }
+
+    public MySqlTableIndex clone() {
+        MySqlTableIndex x = new MySqlTableIndex();
+        if (name != null) {
+            x.setName(name.clone());
+        }
+        x.indexType = indexType;
+        for (SQLSelectOrderByItem column : columns) {
+            SQLSelectOrderByItem c2 = column.clone();
+            c2.setParent(x);
+            x.columns.add(c2);
+        }
+        return x;
+    }
 }

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

@@ -146,4 +146,28 @@ public abstract class OracleSegmentAttributesImpl extends SQLObjectImpl implemen
     public void setCompressForOltp(boolean compressForOltp) {
         this.compressForOltp = compressForOltp;
     }
+
+    public void cloneTo(OracleSegmentAttributesImpl x) {
+        x.pctfree = pctfree;
+        x.pctused = pctused;
+        x.initrans = initrans;
+
+        x.maxtrans = maxtrans;
+        x.pctincrease = pctincrease;
+        x.freeLists = freeLists;
+        x.compress = compress;
+        x.compressLevel = compressLevel;
+        x.compressForOltp = compressForOltp;
+        x.pctthreshold = pctthreshold;
+
+        x.logging = logging;
+
+        if (tablespace != null) {
+            x.setTablespace(tablespace.clone());
+        }
+
+        if (storage != null) {
+            x.setStorage(storage.clone());
+        }
+    }
 }

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

@@ -96,4 +96,22 @@ public class OraclePrimaryKey extends SQLPrimaryKeyImpl implements OracleConstra
         this.initially = initially;
     }
 
+    public void cloneTo(OraclePrimaryKey x) {
+        super.cloneTo(x);
+        if (using != null) {
+            x.setUsing(using.clone());
+        }
+        if (exceptionsInto != null) {
+            x.setExceptionsInto(exceptionsInto.clone());
+        }
+        x.enable = enable;
+        x.initially = initially;
+        x.deferrable = deferrable;
+    }
+
+    public OraclePrimaryKey clone() {
+        OraclePrimaryKey x = new OraclePrimaryKey();
+        cloneTo(x);
+        return x;
+    }
 }

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

@@ -75,4 +75,14 @@ public class OracleSupplementalIdKey extends OracleSQLObjectImpl implements SQLT
     public void setUniqueIndex(boolean uniqueIndex) {
         this.uniqueIndex = uniqueIndex;
     }
+
+    public OracleSupplementalIdKey clone() {
+        OracleSupplementalIdKey x = new OracleSupplementalIdKey();
+        x.all = all;
+        x.primaryKey = primaryKey;
+        x.unique = unique;
+        x.uniqueIndex = uniqueIndex;
+        x.foreignKey = foreignKey;
+        return x;
+    }
 }

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

@@ -16,6 +16,7 @@
 package com.alibaba.druid.sql.dialect.oracle.ast.stmt;
 
 import com.alibaba.druid.sql.ast.SQLName;
+import com.alibaba.druid.sql.ast.statement.SQLColumnDefinition;
 import com.alibaba.druid.sql.ast.statement.SQLTableElement;
 import com.alibaba.druid.sql.dialect.oracle.ast.OracleSQLObjectImpl;
 import com.alibaba.druid.sql.dialect.oracle.visitor.OracleASTVisitor;
@@ -69,4 +70,18 @@ public class OracleSupplementalLogGrp extends OracleSQLObjectImpl implements SQL
     public void setAlways(boolean always) {
         this.always = always;
     }
+
+    public OracleSupplementalLogGrp clone() {
+        OracleSupplementalLogGrp x = new OracleSupplementalLogGrp();
+        if (group != null) {
+            x.setGroup(group.clone());
+        }
+        for (SQLName column : columns) {
+            SQLName c2 = column.clone();
+            c2.setParent(x);
+            x.columns.add(c2);
+        }
+        x.always = always;
+        return x;
+    }
 }

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

@@ -92,4 +92,26 @@ public class OracleUsingIndexClause extends OracleSegmentAttributesImpl implemen
     public List<SQLPartition> getLocalPartitionIndex() {
         return localPartitionIndex;
     }
+
+    public void cloneTo(OracleUsingIndexClause x) {
+        super.cloneTo(x);
+        if (index != null) {
+            x.setIndex(index.clone());
+        }
+        x.enable = enable;
+        x.computeStatistics = computeStatistics;
+        x.reverse = reverse;
+
+        for (SQLPartition p : localPartitionIndex) {
+            SQLPartition p2 = p.clone();
+            p2.setParent(x);
+            x.localPartitionIndex.add(p2);
+        }
+    }
+
+    public OracleUsingIndexClause clone() {
+        OracleUsingIndexClause x = new OracleUsingIndexClause();
+        cloneTo(x);
+        return x;
+    }
 }