improve sql parser

src/main/java/com/alibaba/druid/sql/parser/Token.java

@@ -22,43 +22,55 @@ package com.alibaba.druid.sql.parser;
  * @formatter:off
  */
 public enum Token {
-    EXPLAIN("EXPLAIN"), 
-    FOR("FOR"), 
-    IF("IF"), 
+    SELECT("SELECT"), 
+    DELETE("DELETE"), 
+    INSERT("INSERT"), 
+    UPDATE("UPDATE"), 
+    
+    FROM("FROM"), 
+    HAVING("HAVING"), 
+    WHERE("WHERE"), 
+    ORDER("ORDER"), 
+    BY("BY"),
+    GROUP("GROUP"), 
+    INTO("INTO"), 
+    AS("AS"), 
+    
+    CREATE("CREATE"),
+    ALTER("ALTER"), 
+    DROP("DROP"), 
+    SET("SET"), 
+   
+    NULL("NULL"), 
+    NOT("NOT"), 
+    DISTINCT("DISTINCT"),
+
+    TABLE("TABLE"), 
+    TABLESPACE("TABLESPACE"), 
+    VIEW("VIEW"), 
+    SEQUENCE("SEQUENCE"), 
+    TRIGGER("TRIGGER"), 
+    USER("USER"), 
     INDEX("INDEX"), 
+    SESSION("SESSION"),
+    PROCEDURE("PROCEDURE"),
+    FUNCTION("FUNCTION"),
+    
     PRIMARY("PRIMARY"), 
     KEY("KEY"), 
     DEFAULT("DEFAULT"), 
     CONSTRAINT("CONSTRAINT"), 
     CHECK("CHECK"), 
-    VIEW("VIEW"), 
-    SEQUENCE("SEQUENCE"), 
-    TRIGGER("TRIGGER"), 
-    USER("USER"), 
-    CREATE("CREATE"),
-    ALTER("ALTER"), 
-    DROP("DROP"), 
-    TABLE("TABLE"), 
-    TABLESPACE("TABLESPACE"), 
-    UPDATE("UPDATE"), 
-    SET("SET"), 
-    SELECT("SELECT"), 
-    FROM("FROM"), 
-    WHERE("WHERE"), 
-    ORDER("ORDER"), 
-    BY("BY"),
-    GROUP("GROUP"), 
-    HAVING("HAVING"), 
-    INSERT("INSERT"), 
-    INTO("INTO"), 
-    NULL("NULL"), 
-    NOT("NOT"), 
-    AS("AS"), 
-    DELETE("DELETE"), 
-    DISTINCT("DISTINCT"),
     UNIQUE("UNIQUE"), 
     FOREIGN("FOREIGN"), 
     REFERENCES("REFERENCES"), 
+    
+    EXPLAIN("EXPLAIN"), 
+    FOR("FOR"), 
+    IF("IF"), 
+   
+   
+   
     ALL("ALL"), 
     UNION("UNION"), 
     INTERSECT("INTERSECT"), 
@@ -160,9 +172,6 @@ public enum Token {
     MODE("MODE"),
     WAIT("WAIT"),
     ADVISE("ADVISE"),
-    SESSION("SESSION"),
-    PROCEDURE("PROCEDURE"),
-    FUNCTION("FUNCTION"),
     SYSDATE("SYSDATE"),
     DECLARE("DECLARE"),
     EXCEPTION("EXCEPTION"),