diff --git a/src/main/java/com/alibaba/druid/mapping/MappingContext.java b/src/main/java/com/alibaba/druid/mapping/MappingContext.java
new file mode 100644
index 0000000000..d183193425
--- /dev/null
+++ b/src/main/java/com/alibaba/druid/mapping/MappingContext.java
@@ -0,0 +1,36 @@
+package com.alibaba.druid.mapping;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class MappingContext {
+
+    private List<Object> parameters;
+
+    private boolean      generateAlias = false;
+
+    public MappingContext(){
+        this(new ArrayList<Object>());
+    }
+
+    public MappingContext(List<Object> parameters){
+        this.parameters = parameters;
+    }
+
+    public List<Object> getParameters() {
+        return parameters;
+    }
+
+    public void setParameters(List<Object> parameters) {
+        this.parameters = parameters;
+    }
+
+    public boolean isGenerateAlias() {
+        return generateAlias;
+    }
+
+    public void setGenerateAlias(boolean generateAlias) {
+        this.generateAlias = generateAlias;
+    }
+
+}
diff --git a/src/main/java/com/alibaba/druid/mapping/MappingEngine.java b/src/main/java/com/alibaba/druid/mapping/MappingEngine.java
index 01225e168e..39f3aa3628 100644
--- a/src/main/java/com/alibaba/druid/mapping/MappingEngine.java
+++ b/src/main/java/com/alibaba/druid/mapping/MappingEngine.java
@@ -78,7 +78,11 @@ public class MappingEngine {
     }
     
     public MappingVisitor createMappingVisitor(List<Object> parameters) {
-        return provider.createMappingVisitor(this, parameters);
+        return createMappingVisitor(new MappingContext(parameters));
+    }
+    
+    public MappingVisitor createMappingVisitor(MappingContext context) {
+        return provider.createMappingVisitor(this, context);
     }
 
     public SQLASTOutputVisitor createOutputVisitor(Appendable out) {
@@ -94,9 +98,12 @@ public class MappingEngine {
     }
 
     public String explainToSelectSQL(String sql, List<Object> parameters) {
+        return explainToSelectSQL(sql, new MappingContext(parameters));
+    }
+    public String explainToSelectSQL(String sql, MappingContext context) {
         SQLSelectQueryBlock query = explainToSelectSQLObject(sql);
 
-        MappingVisitor visitor = this.createMappingVisitor(parameters);
+        MappingVisitor visitor = this.createMappingVisitor(context);
         query.accept(visitor);
         visitor.afterResolve();
         afterResole(visitor);
diff --git a/src/main/java/com/alibaba/druid/mapping/spi/MSSQLServerMappingProvider.java b/src/main/java/com/alibaba/druid/mapping/spi/MSSQLServerMappingProvider.java
index d761f64826..25c197cc60 100644
--- a/src/main/java/com/alibaba/druid/mapping/spi/MSSQLServerMappingProvider.java
+++ b/src/main/java/com/alibaba/druid/mapping/spi/MSSQLServerMappingProvider.java
@@ -2,6 +2,7 @@ package com.alibaba.druid.mapping.spi;
 
 import java.util.List;
 
+import com.alibaba.druid.mapping.MappingContext;
 import com.alibaba.druid.mapping.MappingEngine;
 import com.alibaba.druid.sql.ast.expr.SQLNumberExpr;
 import com.alibaba.druid.sql.ast.expr.SQLNumericLiteralExpr;
@@ -27,8 +28,8 @@ public class MSSQLServerMappingProvider implements MappingProvider {
     }
     
     @Override
-    public MappingVisitor createMappingVisitor(MappingEngine engine, List<Object> parameters) {
-        return new MSSQLServerMappingVisitor(engine, parameters);
+    public MappingVisitor createMappingVisitor(MappingEngine engine, MappingContext context) {
+        return new MSSQLServerMappingVisitor(engine, context);
     }
 
     @Override
diff --git a/src/main/java/com/alibaba/druid/mapping/spi/MSSQLServerMappingVisitor.java b/src/main/java/com/alibaba/druid/mapping/spi/MSSQLServerMappingVisitor.java
index 9b9d7a75d3..70c30fe771 100644
--- a/src/main/java/com/alibaba/druid/mapping/spi/MSSQLServerMappingVisitor.java
+++ b/src/main/java/com/alibaba/druid/mapping/spi/MSSQLServerMappingVisitor.java
@@ -1,12 +1,12 @@
 package com.alibaba.druid.mapping.spi;
 
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 
 import com.alibaba.druid.mapping.Entity;
+import com.alibaba.druid.mapping.MappingContext;
 import com.alibaba.druid.mapping.MappingEngine;
 import com.alibaba.druid.mapping.Property;
 import com.alibaba.druid.sql.ast.SQLExpr;
@@ -28,18 +28,18 @@ public class MSSQLServerMappingVisitor extends SQLServerASTVisitorAdapter implem
     private final MappingEngine               engine;
     private final Map<String, SQLTableSource> tableSources   = new LinkedHashMap<String, SQLTableSource>();
 
-    private final List<Object>                parameters;
+    private final MappingContext              context;
     private final List<PropertyValue>         propertyValues = new ArrayList<PropertyValue>();
     private int                               variantIndex   = 0;
     private final List<SQLExpr>               unresolveList  = new ArrayList<SQLExpr>();
 
     public MSSQLServerMappingVisitor(MappingEngine engine){
-        this(engine, Collections.emptyList());
+        this(engine, new MappingContext());
     }
 
-    public MSSQLServerMappingVisitor(MappingEngine engine, List<Object> parameters){
+    public MSSQLServerMappingVisitor(MappingEngine engine, MappingContext context){
         this.engine = engine;
-        this.parameters = parameters;
+        this.context = context;
     }
 
     public MappingEngine getEngine() {
@@ -47,7 +47,11 @@ public class MSSQLServerMappingVisitor extends SQLServerASTVisitorAdapter implem
     }
 
     public List<Object> getParameters() {
-        return parameters;
+        return context.getParameters();
+    }
+    
+    public MappingContext getContext() {
+        return context;
     }
 
     public List<PropertyValue> getPropertyValues() {
@@ -64,12 +68,12 @@ public class MSSQLServerMappingVisitor extends SQLServerASTVisitorAdapter implem
 
     @Override
     public String resolveTableName(Entity entity) {
-        return engine.resolveTableName(entity, parameters);
+        return engine.resolveTableName(entity, context.getParameters());
     }
 
     @Override
     public String resovleColumnName(Entity entity, Property property) {
-        return engine.resovleColumnName(entity, property, parameters);
+        return engine.resovleColumnName(entity, property, context.getParameters());
     }
 
     @Override
@@ -115,7 +119,7 @@ public class MSSQLServerMappingVisitor extends SQLServerASTVisitorAdapter implem
     public boolean visit(SQLVariantRefExpr x) {
         return MappingVisitorUtils.visit(this, x);
     }
-    
+
     @Override
     public boolean visit(SQLSubqueryTableSource x) {
         return MappingVisitorUtils.visit(this, x);
diff --git a/src/main/java/com/alibaba/druid/mapping/spi/MappingProvider.java b/src/main/java/com/alibaba/druid/mapping/spi/MappingProvider.java
index bfec39d0cd..d0c864aca4 100644
--- a/src/main/java/com/alibaba/druid/mapping/spi/MappingProvider.java
+++ b/src/main/java/com/alibaba/druid/mapping/spi/MappingProvider.java
@@ -2,6 +2,7 @@ package com.alibaba.druid.mapping.spi;
 
 import java.util.List;
 
+import com.alibaba.druid.mapping.MappingContext;
 import com.alibaba.druid.mapping.MappingEngine;
 import com.alibaba.druid.sql.ast.statement.SQLDeleteStatement;
 import com.alibaba.druid.sql.ast.statement.SQLInsertStatement;
@@ -14,7 +15,7 @@ public interface MappingProvider {
 
     MappingVisitor createMappingVisitor(MappingEngine engine);
     
-    MappingVisitor createMappingVisitor(MappingEngine engine, List<Object> parameters);
+    MappingVisitor createMappingVisitor(MappingEngine engine, MappingContext context);
     
     ExportParameterVisitor createExportParameterVisitor(List<Object> parameters);
 
diff --git a/src/main/java/com/alibaba/druid/mapping/spi/MappingVisitor.java b/src/main/java/com/alibaba/druid/mapping/spi/MappingVisitor.java
index b5764e398f..d567385238 100644
--- a/src/main/java/com/alibaba/druid/mapping/spi/MappingVisitor.java
+++ b/src/main/java/com/alibaba/druid/mapping/spi/MappingVisitor.java
@@ -4,6 +4,7 @@ import java.util.List;
 import java.util.Map;
 
 import com.alibaba.druid.mapping.Entity;
+import com.alibaba.druid.mapping.MappingContext;
 import com.alibaba.druid.mapping.MappingEngine;
 import com.alibaba.druid.mapping.Property;
 import com.alibaba.druid.sql.ast.SQLExpr;
@@ -14,6 +15,8 @@ public interface MappingVisitor extends SQLASTVisitor {
     MappingEngine getEngine();
     
     List<Object> getParameters();
+    
+    MappingContext getContext();
 
     Entity getFirstEntity();
 
diff --git a/src/main/java/com/alibaba/druid/mapping/spi/MappingVisitorUtils.java b/src/main/java/com/alibaba/druid/mapping/spi/MappingVisitorUtils.java
index 8f9794387c..6c6f4b9e69 100644
--- a/src/main/java/com/alibaba/druid/mapping/spi/MappingVisitorUtils.java
+++ b/src/main/java/com/alibaba/druid/mapping/spi/MappingVisitorUtils.java
@@ -93,7 +93,7 @@ public class MappingVisitorUtils {
 
         if (x.getParent() instanceof SQLSelectItem) {
             SQLSelectItem selectItem = (SQLSelectItem) x.getParent();
-            if (selectItem.getAlias() == null) {
+            if (visitor.getContext().isGenerateAlias() && selectItem.getAlias() == null) {
                 selectItem.setAlias('"' + property.getName() + '"');
             }
         }
@@ -129,9 +129,9 @@ public class MappingVisitorUtils {
         x.putAttribute("mapping.property", property);
         x.putAttribute("mapping.entity", propertyEntity);
 
-        if (x.getParent() instanceof SQLSelectItem) {
+        if (visitor.getContext().isGenerateAlias() && x.getParent() instanceof SQLSelectItem) {
             SQLSelectItem selectItem = (SQLSelectItem) x.getParent();
-            if (selectItem.getAlias() == null) {
+            if (visitor.getContext().isGenerateAlias() && selectItem.getAlias() == null) {
                 selectItem.setAlias('"' + property.getName() + '"');
             }
         }
diff --git a/src/main/java/com/alibaba/druid/mapping/spi/MySqlMappingProvider.java b/src/main/java/com/alibaba/druid/mapping/spi/MySqlMappingProvider.java
index 79a744fe14..cd0a02201e 100644
--- a/src/main/java/com/alibaba/druid/mapping/spi/MySqlMappingProvider.java
+++ b/src/main/java/com/alibaba/druid/mapping/spi/MySqlMappingProvider.java
@@ -2,6 +2,7 @@ package com.alibaba.druid.mapping.spi;
 
 import java.util.List;
 
+import com.alibaba.druid.mapping.MappingContext;
 import com.alibaba.druid.mapping.MappingEngine;
 import com.alibaba.druid.sql.ast.expr.SQLIntegerExpr;
 import com.alibaba.druid.sql.ast.expr.SQLNumericLiteralExpr;
@@ -26,8 +27,8 @@ public class MySqlMappingProvider implements MappingProvider {
     }
     
     @Override
-    public MappingVisitor createMappingVisitor(MappingEngine engine, List<Object> parameters) {
-        return new MySqlMappingVisitor(engine, parameters);
+    public MappingVisitor createMappingVisitor(MappingEngine engine, MappingContext context) {
+        return new MySqlMappingVisitor(engine, context);
     }
 
     @Override
diff --git a/src/main/java/com/alibaba/druid/mapping/spi/MySqlMappingVisitor.java b/src/main/java/com/alibaba/druid/mapping/spi/MySqlMappingVisitor.java
index 4227b978ef..ef7faa07c3 100644
--- a/src/main/java/com/alibaba/druid/mapping/spi/MySqlMappingVisitor.java
+++ b/src/main/java/com/alibaba/druid/mapping/spi/MySqlMappingVisitor.java
@@ -1,12 +1,12 @@
 package com.alibaba.druid.mapping.spi;
 
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 
 import com.alibaba.druid.mapping.Entity;
+import com.alibaba.druid.mapping.MappingContext;
 import com.alibaba.druid.mapping.MappingEngine;
 import com.alibaba.druid.mapping.Property;
 import com.alibaba.druid.sql.ast.SQLExpr;
@@ -28,18 +28,18 @@ public class MySqlMappingVisitor extends MySqlASTVisitorAdapter implements Mappi
     private final MappingEngine               engine;
     private final Map<String, SQLTableSource> tableSources   = new LinkedHashMap<String, SQLTableSource>();
 
-    private final List<Object>                parameters;
+    private final MappingContext              context;
     private final List<PropertyValue>         propertyValues = new ArrayList<PropertyValue>();
     private int                               variantIndex   = 0;
     private final List<SQLExpr>               unresolveList  = new ArrayList<SQLExpr>();
 
     public MySqlMappingVisitor(MappingEngine engine){
-        this(engine, Collections.emptyList());
+        this(engine, new MappingContext());
     }
 
-    public MySqlMappingVisitor(MappingEngine engine, List<Object> parameters){
+    public MySqlMappingVisitor(MappingEngine engine, MappingContext context){
         this.engine = engine;
-        this.parameters = parameters;
+        this.context = context;
     }
 
     public MappingEngine getEngine() {
@@ -47,7 +47,11 @@ public class MySqlMappingVisitor extends MySqlASTVisitorAdapter implements Mappi
     }
 
     public List<Object> getParameters() {
-        return parameters;
+        return context.getParameters();
+    }
+
+    public MappingContext getContext() {
+        return context;
     }
 
     public List<PropertyValue> getPropertyValues() {
@@ -64,12 +68,12 @@ public class MySqlMappingVisitor extends MySqlASTVisitorAdapter implements Mappi
 
     @Override
     public String resolveTableName(Entity entity) {
-        return engine.resolveTableName(entity, parameters);
+        return engine.resolveTableName(entity, context.getParameters());
     }
 
     @Override
     public String resovleColumnName(Entity entity, Property property) {
-        return engine.resovleColumnName(entity, property, parameters);
+        return engine.resovleColumnName(entity, property, context.getParameters());
     }
 
     public Entity getFirstEntity() {
@@ -109,7 +113,7 @@ public class MySqlMappingVisitor extends MySqlASTVisitorAdapter implements Mappi
     public boolean visit(SQLBinaryOpExpr x) {
         return MappingVisitorUtils.visit(this, x);
     }
-    
+
     @Override
     public boolean visit(SQLVariantRefExpr x) {
         return MappingVisitorUtils.visit(this, x);
@@ -129,16 +133,16 @@ public class MySqlMappingVisitor extends MySqlASTVisitorAdapter implements Mappi
     public boolean visit(SQLExprTableSource x) {
         return MappingVisitorUtils.visit(this, x);
     }
-    
+
     @Override
     public int getAndIncrementVariantIndex() {
         return variantIndex++;
     }
-    
+
     public int getVariantIndex() {
         return variantIndex;
     }
-    
+
     public List<SQLExpr> getUnresolveList() {
         return unresolveList;
     }
diff --git a/src/main/java/com/alibaba/druid/mapping/spi/OracleMappingProvider.java b/src/main/java/com/alibaba/druid/mapping/spi/OracleMappingProvider.java
index afb0859165..6ce116f22b 100644
--- a/src/main/java/com/alibaba/druid/mapping/spi/OracleMappingProvider.java
+++ b/src/main/java/com/alibaba/druid/mapping/spi/OracleMappingProvider.java
@@ -2,6 +2,7 @@ package com.alibaba.druid.mapping.spi;
 
 import java.util.List;
 
+import com.alibaba.druid.mapping.MappingContext;
 import com.alibaba.druid.mapping.MappingEngine;
 import com.alibaba.druid.sql.ast.statement.SQLInsertStatement;
 import com.alibaba.druid.sql.ast.statement.SQLSelectQueryBlock;
@@ -23,8 +24,8 @@ public class OracleMappingProvider implements MappingProvider {
     }
     
     @Override
-    public MappingVisitor createMappingVisitor(MappingEngine engine, List<Object> parameters) {
-        return new OracleMappingVisitor(engine, parameters);
+    public MappingVisitor createMappingVisitor(MappingEngine engine, MappingContext context) {
+        return new OracleMappingVisitor(engine, context);
     }
 
     @Override
diff --git a/src/main/java/com/alibaba/druid/mapping/spi/OracleMappingVisitor.java b/src/main/java/com/alibaba/druid/mapping/spi/OracleMappingVisitor.java
index 37b97bcfd6..a12c0da24c 100644
--- a/src/main/java/com/alibaba/druid/mapping/spi/OracleMappingVisitor.java
+++ b/src/main/java/com/alibaba/druid/mapping/spi/OracleMappingVisitor.java
@@ -1,12 +1,12 @@
 package com.alibaba.druid.mapping.spi;
 
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 
 import com.alibaba.druid.mapping.Entity;
+import com.alibaba.druid.mapping.MappingContext;
 import com.alibaba.druid.mapping.MappingEngine;
 import com.alibaba.druid.mapping.Property;
 import com.alibaba.druid.sql.ast.SQLExpr;
@@ -30,18 +30,18 @@ public class OracleMappingVisitor extends OracleASTVisitorAdapter implements Map
     private final MappingEngine               engine;
     private final Map<String, SQLTableSource> tableSources = new LinkedHashMap<String, SQLTableSource>();
 
-    private final List<Object>                parameters;
+    private final MappingContext              context;
     private final List<PropertyValue>         propertyValues = new ArrayList<PropertyValue>();
     private int                               variantIndex   = 0;
     private final List<SQLExpr>               unresolveList  = new ArrayList<SQLExpr>();
 
     public OracleMappingVisitor(MappingEngine engine){
-        this(engine, Collections.emptyList());
+        this(engine, new MappingContext());
     }
 
-    public OracleMappingVisitor(MappingEngine engine, List<Object> parameters){
+    public OracleMappingVisitor(MappingEngine engine, MappingContext context){
         this.engine = engine;
-        this.parameters = parameters;
+        this.context = context;
     }
 
     public MappingEngine getEngine() {
@@ -49,7 +49,11 @@ public class OracleMappingVisitor extends OracleASTVisitorAdapter implements Map
     }
 
     public List<Object> getParameters() {
-        return parameters;
+        return context.getParameters();
+    }
+    
+    public MappingContext getContext() {
+        return context;
     }
     
     public List<PropertyValue> getPropertyValues() {
@@ -66,12 +70,12 @@ public class OracleMappingVisitor extends OracleASTVisitorAdapter implements Map
 
     @Override
     public String resolveTableName(Entity entity) {
-        return engine.resolveTableName(entity, parameters);
+        return engine.resolveTableName(entity, context.getParameters());
     }
 
     @Override
     public String resovleColumnName(Entity entity, Property property) {
-        return engine.resovleColumnName(entity, property, parameters);
+        return engine.resovleColumnName(entity, property, context.getParameters());
     }
 
     public Entity getFirstEntity() {
diff --git a/src/main/java/com/alibaba/druid/proxy/jdbc/StatementProxyImpl.java b/src/main/java/com/alibaba/druid/proxy/jdbc/StatementProxyImpl.java
index 57754885c2..64ed278f70 100644
--- a/src/main/java/com/alibaba/druid/proxy/jdbc/StatementProxyImpl.java
+++ b/src/main/java/com/alibaba/druid/proxy/jdbc/StatementProxyImpl.java
@@ -29,8 +29,6 @@ import java.util.Map;
 import com.alibaba.druid.filter.FilterChain;
 import com.alibaba.druid.filter.FilterChainImpl;
 import com.alibaba.druid.stat.JdbcSqlStat;
-import com.alibaba.druid.stat.JdbcStatContext;
-import com.alibaba.druid.stat.JdbcStatManager;
 
 /**
  * @author wenshao<szujobs@hotmail.com>
diff --git a/src/main/java/com/alibaba/druid/sql/dialect/mysql/visitor/MySqlOutputVisitor.java b/src/main/java/com/alibaba/druid/sql/dialect/mysql/visitor/MySqlOutputVisitor.java
index 48d98e9420..acb3909377 100644
--- a/src/main/java/com/alibaba/druid/sql/dialect/mysql/visitor/MySqlOutputVisitor.java
+++ b/src/main/java/com/alibaba/druid/sql/dialect/mysql/visitor/MySqlOutputVisitor.java
@@ -28,7 +28,6 @@ import com.alibaba.druid.sql.ast.statement.SQLColumnConstraint;
 import com.alibaba.druid.sql.ast.statement.SQLColumnDefinition;
 import com.alibaba.druid.sql.ast.statement.SQLCreateTableStatement;
 import com.alibaba.druid.sql.ast.statement.SQLSelectQueryBlock;
-import com.alibaba.druid.sql.ast.statement.SQLUpdateSetItem;
 import com.alibaba.druid.sql.ast.statement.SQLUpdateStatement;
 import com.alibaba.druid.sql.dialect.mysql.ast.MySqlKey;
 import com.alibaba.druid.sql.dialect.mysql.ast.MySqlPrimaryKey;
diff --git a/src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/PGAnalyticWindowing.java b/src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/PGAnalyticWindowing.java
index 852a93b62e..1fb292fc06 100644
--- a/src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/PGAnalyticWindowing.java
+++ b/src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/PGAnalyticWindowing.java
@@ -17,7 +17,6 @@ package com.alibaba.druid.sql.dialect.postgresql.ast;
 
 import com.alibaba.druid.sql.ast.SQLExpr;
 import com.alibaba.druid.sql.ast.SQLObjectImpl;
-import com.alibaba.druid.sql.dialect.oracle.visitor.OracleASTVisitor;
 import com.alibaba.druid.sql.dialect.postgresql.ast.expr.PGExpr;
 import com.alibaba.druid.sql.dialect.postgresql.visitor.PGASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
diff --git a/src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/expr/PGAnalytic.java b/src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/expr/PGAnalytic.java
index 2e6dc18168..41649f0954 100644
--- a/src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/expr/PGAnalytic.java
+++ b/src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/expr/PGAnalytic.java
@@ -20,7 +20,6 @@ import java.util.List;
 
 import com.alibaba.druid.sql.ast.SQLExpr;
 import com.alibaba.druid.sql.ast.SQLObjectImpl;
-import com.alibaba.druid.sql.dialect.postgresql.ast.PGAnalyticWindowing;
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGOrderBy;
 import com.alibaba.druid.sql.dialect.postgresql.visitor.PGASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
diff --git a/src/main/java/com/alibaba/druid/sql/dialect/postgresql/parser/PGExprParser.java b/src/main/java/com/alibaba/druid/sql/dialect/postgresql/parser/PGExprParser.java
index 945a2393c0..0e7f8017e6 100644
--- a/src/main/java/com/alibaba/druid/sql/dialect/postgresql/parser/PGExprParser.java
+++ b/src/main/java/com/alibaba/druid/sql/dialect/postgresql/parser/PGExprParser.java
@@ -1,9 +1,6 @@
 package com.alibaba.druid.sql.dialect.postgresql.parser;
 
 import com.alibaba.druid.sql.ast.expr.SQLAggregateExpr;
-import com.alibaba.druid.sql.ast.expr.SQLIdentifierExpr;
-import com.alibaba.druid.sql.dialect.oracle.ast.OracleOrderBy;
-import com.alibaba.druid.sql.dialect.oracle.ast.expr.OracleAnalyticWindowing;
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGAggregateExpr;
 import com.alibaba.druid.sql.dialect.postgresql.ast.PGOrderBy;
 import com.alibaba.druid.sql.dialect.postgresql.ast.expr.PGAnalytic;