diff --git a/src/main/java/com/alibaba/druid/sql/ast/expr/SQLAggregateExpr.java b/src/main/java/com/alibaba/druid/sql/ast/expr/SQLAggregateExpr.java
index 8abf08b232..f928dde609 100644
--- a/src/main/java/com/alibaba/druid/sql/ast/expr/SQLAggregateExpr.java
+++ b/src/main/java/com/alibaba/druid/sql/ast/expr/SQLAggregateExpr.java
@@ -27,16 +27,15 @@ public class SQLAggregateExpr extends SQLExprImpl implements Serializable {
 
     private static final long     serialVersionUID = 1L;
     protected String              methodName;
-    protected int                 option;
+    protected Option              option;
     protected final List<SQLExpr> arguments        = new ArrayList<SQLExpr>();
 
     public SQLAggregateExpr(String methodName){
 
         this.methodName = methodName;
-        this.option = 1;
     }
 
-    public SQLAggregateExpr(String methodName, int option){
+    public SQLAggregateExpr(String methodName, Option option){
         this.methodName = methodName;
         this.option = option;
     }
@@ -49,11 +48,11 @@ public class SQLAggregateExpr extends SQLExprImpl implements Serializable {
         this.methodName = methodName;
     }
 
-    public int getOption() {
+    public Option getOption() {
         return this.option;
     }
 
-    public void setOption(int option) {
+    public void setOption(Option option) {
         this.option = option;
     }
 
@@ -86,7 +85,7 @@ public class SQLAggregateExpr extends SQLExprImpl implements Serializable {
         int result = 1;
         result = prime * result + ((arguments == null) ? 0 : arguments.hashCode());
         result = prime * result + ((methodName == null) ? 0 : methodName.hashCode());
-        result = prime * result + option;
+        result = prime * result + ((option == null) ? 0 : option.hashCode());
         return result;
     }
 
@@ -121,4 +120,8 @@ public class SQLAggregateExpr extends SQLExprImpl implements Serializable {
         }
         return true;
     }
+
+    public static enum Option {
+        DISTINCT, ALL
+    }
 }
diff --git a/src/main/java/com/alibaba/druid/sql/dialect/oracle/ast/expr/OracleAggregateExpr.java b/src/main/java/com/alibaba/druid/sql/dialect/oracle/ast/expr/OracleAggregateExpr.java
index f1619e5157..c87bc58921 100644
--- a/src/main/java/com/alibaba/druid/sql/dialect/oracle/ast/expr/OracleAggregateExpr.java
+++ b/src/main/java/com/alibaba/druid/sql/dialect/oracle/ast/expr/OracleAggregateExpr.java
@@ -49,7 +49,7 @@ public class OracleAggregateExpr extends SQLAggregateExpr implements Serializabl
         super(methodName);
     }
 
-    public OracleAggregateExpr(String methodName, int option){
+    public OracleAggregateExpr(String methodName, Option option){
         super(methodName, option);
     }
 
diff --git a/src/main/java/com/alibaba/druid/sql/dialect/oracle/parser/OracleExprParser.java b/src/main/java/com/alibaba/druid/sql/dialect/oracle/parser/OracleExprParser.java
index bce3bfc56d..a71bab7efe 100644
--- a/src/main/java/com/alibaba/druid/sql/dialect/oracle/parser/OracleExprParser.java
+++ b/src/main/java/com/alibaba/druid/sql/dialect/oracle/parser/OracleExprParser.java
@@ -22,6 +22,7 @@ import com.alibaba.druid.sql.ast.SQLDataTypeImpl;
 import com.alibaba.druid.sql.ast.SQLExpr;
 import com.alibaba.druid.sql.ast.SQLName;
 import com.alibaba.druid.sql.ast.SQLOrderingSpecification;
+import com.alibaba.druid.sql.ast.expr.SQLAggregateExpr;
 import com.alibaba.druid.sql.ast.expr.SQLBinaryOpExpr;
 import com.alibaba.druid.sql.ast.expr.SQLBinaryOperator;
 import com.alibaba.druid.sql.ast.expr.SQLCharExpr;
@@ -524,9 +525,11 @@ public class OracleExprParser extends SQLExprParser {
         return null;
     }
 
-    protected OracleAggregateExpr parseAggregateExpr(String method_name) {
+    protected OracleAggregateExpr parseAggregateExpr(String methodName) {
         boolean unique = false;
         
+        methodName = methodName.toUpperCase();
+        
         if (lexer.token() == Token.UNIQUE) {
             lexer.nextToken();
             unique = true;
@@ -534,13 +537,13 @@ public class OracleExprParser extends SQLExprParser {
         
         OracleAggregateExpr aggregateExpr;
         if (lexer.token() == (Token.ALL)) {
-            aggregateExpr = new OracleAggregateExpr(method_name, 1);
+            aggregateExpr = new OracleAggregateExpr(methodName, SQLAggregateExpr.Option.ALL);
             lexer.nextToken();
         } else if (lexer.token() == (Token.DISTINCT)) {
-            aggregateExpr = new OracleAggregateExpr(method_name, 0);
+            aggregateExpr = new OracleAggregateExpr(methodName, SQLAggregateExpr.Option.DISTINCT);
             lexer.nextToken();
         } else {
-            aggregateExpr = new OracleAggregateExpr(method_name, 1);
+            aggregateExpr = new OracleAggregateExpr(methodName);
         }
         aggregateExpr.setUnique(unique);
         exprList(aggregateExpr.getArguments());
diff --git a/src/main/java/com/alibaba/druid/sql/dialect/oracle/visitor/OracleOutputVisitor.java b/src/main/java/com/alibaba/druid/sql/dialect/oracle/visitor/OracleOutputVisitor.java
index d36d120b78..6c2c2c47cb 100644
--- a/src/main/java/com/alibaba/druid/sql/dialect/oracle/visitor/OracleOutputVisitor.java
+++ b/src/main/java/com/alibaba/druid/sql/dialect/oracle/visitor/OracleOutputVisitor.java
@@ -211,6 +211,12 @@ public class OracleOutputVisitor extends SQLASTOutputVisitor implements OracleAS
     public boolean visit(OracleAggregateExpr expr) {
         print(expr.getMethodName());
         print("(");
+        
+        if (expr.getOption() != null) {
+            print(expr.getOption().toString());
+            print(' ');
+        }
+        
         if (expr.isUnique()) {
             print("UNIQUE ");
         }
diff --git a/src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/PGAggregateExpr.java b/src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/PGAggregateExpr.java
index 390aed24a9..8a6cf87318 100644
--- a/src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/PGAggregateExpr.java
+++ b/src/main/java/com/alibaba/druid/sql/dialect/postgresql/ast/PGAggregateExpr.java
@@ -20,7 +20,7 @@ public class PGAggregateExpr extends SQLAggregateExpr implements PGSQLObject {
 
 	private static final long serialVersionUID = 1L;
 
-	public PGAggregateExpr(String methodName, int option) {
+	public PGAggregateExpr(String methodName, Option option) {
 		super(methodName, option);
 	}
 
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 4d4ec91164..5ace50df14 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
@@ -19,16 +19,18 @@ public class PGExprParser extends SQLExprParser{
         super(lexer);
     }
     
-    protected SQLAggregateExpr parseAggregateExpr(String method_name) throws ParserException {
+    protected SQLAggregateExpr parseAggregateExpr(String methodName) throws ParserException {
+        methodName = methodName.toUpperCase();
+        
         PGAggregateExpr aggregateExpr;
         if (lexer.token() == Token.ALL) {
-            aggregateExpr = new PGAggregateExpr(method_name, 1);
+            aggregateExpr = new PGAggregateExpr(methodName, SQLAggregateExpr.Option.ALL);
             lexer.nextToken();
         } else if (lexer.token() == Token.DISTINCT) {
-            aggregateExpr = new PGAggregateExpr(method_name, 0);
+            aggregateExpr = new PGAggregateExpr(methodName, SQLAggregateExpr.Option.DISTINCT);
             lexer.nextToken();
         } else {
-            aggregateExpr = new PGAggregateExpr(method_name, 1);
+            aggregateExpr = new PGAggregateExpr(methodName);
         }
 
         exprList(aggregateExpr.getArguments());
diff --git a/src/main/java/com/alibaba/druid/sql/dialect/postgresql/visitor/PGOutputVisitor.java b/src/main/java/com/alibaba/druid/sql/dialect/postgresql/visitor/PGOutputVisitor.java
index 38ddec0c02..23784425f3 100644
--- a/src/main/java/com/alibaba/druid/sql/dialect/postgresql/visitor/PGOutputVisitor.java
+++ b/src/main/java/com/alibaba/druid/sql/dialect/postgresql/visitor/PGOutputVisitor.java
@@ -433,12 +433,21 @@ public class PGOutputVisitor extends SQLASTOutputVisitor implements PGASTVisitor
     @Override
     public boolean visit(PGAggregateExpr x) {
         print(x.getMethodName());
+        
         print("(");
+        
+        if (x.getOption() != null) {
+            print(x.getOption().toString());
+            print(' ');
+        }
+        
         printAndAccept(x.getArguments(), ", ");
         print(")");
+        
         if (x.getOver() != null) {
             x.getOver().accept(this);
         }
+        
         return false;
     }
 
diff --git a/src/main/java/com/alibaba/druid/sql/parser/SQLExprParser.java b/src/main/java/com/alibaba/druid/sql/parser/SQLExprParser.java
index 3d8f089750..9c5aa476d1 100644
--- a/src/main/java/com/alibaba/druid/sql/parser/SQLExprParser.java
+++ b/src/main/java/com/alibaba/druid/sql/parser/SQLExprParser.java
@@ -675,16 +675,18 @@ public class SQLExprParser extends SQLParser {
         return false;
     }
 
-    protected SQLAggregateExpr parseAggregateExpr(String method_name) throws ParserException {
+    protected SQLAggregateExpr parseAggregateExpr(String methodName) throws ParserException {
+        methodName = methodName.toUpperCase();
+        
         SQLAggregateExpr aggregateExpr;
         if (lexer.token() == Token.ALL) {
-            aggregateExpr = new SQLAggregateExpr(method_name, 1);
+            aggregateExpr = new SQLAggregateExpr(methodName, SQLAggregateExpr.Option.ALL);
             lexer.nextToken();
         } else if (lexer.token() == Token.DISTINCT) {
-            aggregateExpr = new SQLAggregateExpr(method_name, 0);
+            aggregateExpr = new SQLAggregateExpr(methodName, SQLAggregateExpr.Option.DISTINCT);
             lexer.nextToken();
         } else {
-            aggregateExpr = new SQLAggregateExpr(method_name, 1);
+            aggregateExpr = new SQLAggregateExpr(methodName);
         }
 
         exprList(aggregateExpr.getArguments());
diff --git a/src/main/java/com/alibaba/druid/sql/visitor/SQLASTOutputVisitor.java b/src/main/java/com/alibaba/druid/sql/visitor/SQLASTOutputVisitor.java
index 7686462365..3ea42f7244 100644
--- a/src/main/java/com/alibaba/druid/sql/visitor/SQLASTOutputVisitor.java
+++ b/src/main/java/com/alibaba/druid/sql/visitor/SQLASTOutputVisitor.java
@@ -426,6 +426,12 @@ public class SQLASTOutputVisitor extends SQLASTVisitorAdapter {
     public boolean visit(SQLAggregateExpr x) {
         print(x.getMethodName());
         print("(");
+        
+        if (x.getOption() != null) {
+            print(x.getOption().toString());
+            print(' ');
+        }
+        
         printAndAccept(x.getArguments(), ", ");
         print(")");
         return false;
diff --git a/src/main/java/com/alibaba/druid/stat/JdbcStatManagerFactoryBean.java b/src/main/java/com/alibaba/druid/stat/JdbcStatManagerFactoryBean.java
index 9bc3f85a4b..68cc92360f 100644
--- a/src/main/java/com/alibaba/druid/stat/JdbcStatManagerFactoryBean.java
+++ b/src/main/java/com/alibaba/druid/stat/JdbcStatManagerFactoryBean.java
@@ -17,10 +17,10 @@ package com.alibaba.druid.stat;
 
 import org.springframework.beans.factory.FactoryBean;
 
-public class JdbcStatManagerFactoryBean implements FactoryBean {
+public class JdbcStatManagerFactoryBean implements FactoryBean<JdbcStatManager> {
 
     @Override
-    public Object getObject() throws Exception {
+    public JdbcStatManager getObject() throws Exception {
         return JdbcStatManager.getInstance();
     }
 
diff --git a/src/main/java/com/alibaba/druid/support/spring/MBeanServerFactoryBean.java b/src/main/java/com/alibaba/druid/support/spring/MBeanServerFactoryBean.java
index 23e117e639..5ba4e3e697 100644
--- a/src/main/java/com/alibaba/druid/support/spring/MBeanServerFactoryBean.java
+++ b/src/main/java/com/alibaba/druid/support/spring/MBeanServerFactoryBean.java
@@ -6,7 +6,7 @@ import javax.management.MBeanServer;
 
 import org.springframework.beans.factory.FactoryBean;
 
-public class MBeanServerFactoryBean implements FactoryBean {
+public class MBeanServerFactoryBean implements FactoryBean<MBeanServer> {
 
     public MBeanServer getObject() throws Exception {
         return ManagementFactory.getPlatformMBeanServer();
diff --git a/src/test/java/com/alibaba/druid/bvt/sql/DistinctTest.java b/src/test/java/com/alibaba/druid/bvt/sql/DistinctTest.java
new file mode 100644
index 0000000000..1eb807dd2e
--- /dev/null
+++ b/src/test/java/com/alibaba/druid/bvt/sql/DistinctTest.java
@@ -0,0 +1,28 @@
+package com.alibaba.druid.bvt.sql;
+
+import junit.framework.Assert;
+import junit.framework.TestCase;
+
+import com.alibaba.druid.sql.SQLUtils;
+import com.alibaba.druid.util.JdbcUtils;
+
+
+public class DistinctTest extends TestCase {
+    private String sql = "select count(distinct *) from t";
+    
+    public void test_mysql() throws Exception {
+        Assert.assertEquals("SELECT COUNT(DISTINCT *)\nFROM t", SQLUtils.format(sql, JdbcUtils.MYSQL));
+    }
+    
+    public void test_oracle() throws Exception {
+        Assert.assertEquals("SELECT COUNT(DISTINCT *)\nFROM t", SQLUtils.format(sql, JdbcUtils.ORACLE));
+    }
+    
+    public void test_postgres() throws Exception {
+        Assert.assertEquals("SELECT COUNT(DISTINCT *)\nFROM t", SQLUtils.format(sql, JdbcUtils.POSTGRESQL));
+    }
+    
+    public void test_sql92() throws Exception {
+        Assert.assertEquals("SELECT COUNT(DISTINCT *)\nFROM t", SQLUtils.format(sql, null));
+    }
+}