查询结果的顺序,该怎么处理

查询结果的顺序
select * from X
where X.a like '11%'
or X.a like '12%'
or X.a like '13%'
or ……

查询结果是：
12
13
11

我想让查询出来的结果是按照我select语句中like的先后顺序显示，也就是
11
12
13

为什么用上面的select不行呢？

[解决办法]
select * from X
where X.a like '11%'
or X.a like '12%'
or X.a like '13%'
or …… 
order by a
[解决办法]
select a from (
select a,rownum rn from X 
where X.a like '11%'
union 
select a,rownum+1 rn from X 
where X.a like '12%' 
select a,rownum+2 rn from X 
where X.a like '13%' )
order by rn
[解决办法]
select a from ( 
select a,rownum rn from X 
where X.a like '11%' 
union 
select a,rownum+1 rn from X 
where X.a like '12%' 
union 
.
.
.
union 
select a,rownum+1 rn from X 
where X.a like 'XX%'
[解决办法]
顶顶
[解决办法]
select a from ( 
select a,rownum rn from X 
where X.a like '11%' 
union 
select a,rownum+1 rn from X 
where X.a like '12%' 
union 
. 
. 
. 
union 
select a,rownum+1 rn from X 
where X.a like 'XX%')