修正运算符优先级别处理不当的问题

git-svn-id: http://code.alibabatech.com/svn/druid/trunk@160 b9813039-fb51-4c41-a8b9-e21c2acb5095

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

@@ -29,6 +29,7 @@ public class SQLInsertStatement extends SQLStatementImpl {
 
     private static final long   serialVersionUID = 1L;
     private SQLName             tableName;
+    private String              alias;
 
     private final List<SQLExpr> columns          = new ArrayList<SQLExpr>();
     private ValuesClause        values;
@@ -38,6 +39,14 @@ public class SQLInsertStatement extends SQLStatementImpl {
 
     }
 
+    public String getAlias() {
+        return alias;
+    }
+
+    public void setAlias(String alias) {
+        this.alias = alias;
+    }
+
     public SQLName getTableName() {
         return tableName;
     }

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

@@ -51,7 +51,10 @@ public class SQLSubqueryTableSource extends SQLTableSource {
 
     @Override
     protected void accept0(SQLASTVisitor visitor) {
-        throw new UnsupportedOperationException();
+       if (visitor.visit(this)) {
+           acceptChild(visitor, select);
+       }
+       visitor.endVisit(this);
     }
 
     public void output(StringBuffer buf) {

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

@@ -0,0 +1,18 @@
+package com.alibaba.druid.sql.ast.statement;
+
+public enum SQLUnionOperator {
+    UNION("UNION"),
+    UNION_ALL("UNION ALL"),
+    MINUS("MINUS"),
+    INTERSECT("INTERSECT");
+    
+    public final String name;
+    
+    private SQLUnionOperator(String name) {
+        this.name = name;
+    }
+    
+    public String toString() {
+        return name;
+    }
+}

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

@@ -23,7 +23,15 @@ public class SQLUnionQuery extends SQLSelectQuery {
 
     private SQLSelectQuery    left;
     private SQLSelectQuery    right;
-    private boolean           all;
+    private SQLUnionOperator  operator         = SQLUnionOperator.UNION;
+
+    public SQLUnionOperator getOperator() {
+        return operator;
+    }
+
+    public void setOperator(SQLUnionOperator operator) {
+        this.operator = operator;
+    }
 
     public SQLUnionQuery(){
 
@@ -45,14 +53,6 @@ public class SQLUnionQuery extends SQLSelectQuery {
         this.right = right;
     }
 
-    public boolean isAll() {
-        return all;
-    }
-
-    public void setAll(boolean all) {
-        this.all = all;
-    }
-
     @Override
     protected void accept0(SQLASTVisitor visitor) {
         if (visitor.visit(this)) {