improved sql parser.

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

@@ -20,6 +20,7 @@ import java.util.List;
 
 import com.alibaba.druid.sql.ast.SQLName;
 import com.alibaba.druid.sql.ast.statement.SQLDeleteStatement;
+import com.alibaba.druid.sql.dialect.mysql.ast.statement.MySqlDeleteStatement;
 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;
@@ -28,7 +29,6 @@ import com.alibaba.druid.util.JdbcConstants;
 public class PGDeleteStatement extends SQLDeleteStatement implements PGSQLStatement {
 
     private PGWithClause  with;
-    private boolean       only  = false;
     private List<SQLName> using = new ArrayList<SQLName>(2);
     private boolean       returning;
     private String        alias;
@@ -61,13 +61,7 @@ public class PGDeleteStatement extends SQLDeleteStatement implements PGSQLStatem
         this.using = using;
     }
 
-    public boolean isOnly() {
-        return only;
-    }
 
-    public void setOnly(boolean only) {
-        this.only = only;
-    }
 
     public PGWithClause getWith() {
         return with;
@@ -93,4 +87,21 @@ public class PGDeleteStatement extends SQLDeleteStatement implements PGSQLStatem
         visitor.endVisit(this);
     }
 
+    public PGDeleteStatement clone() {
+        PGDeleteStatement x = new PGDeleteStatement();
+        cloneTo(x);
+
+        if (with != null) {
+            x.setWith(with.clone());
+        }
+        for (SQLName item : using) {
+            SQLName item2 = item.clone();
+            item2.setParent(x);
+            x.using.add(item2);
+        }
+        x.returning = returning;
+        x.alias = alias;
+
+        return x;
+    }
 }