很简单，却很奇怪的问题，关于order by

A表里就一个字段a。select * from A
排序是这样的（数据本身没有双引号）
"21c_tut"
"21cadse"
"21c-buk"
"21CG-5F"
"21c-gij"
"21cg-pc"
"21cg-pc"
"21cg-pc"
"21CG-PR"
"21CG-2F"
"21CG-2F"
"21CG-5F"
"21CG-5F"
"21CG-5F"
"21CG-5F"
"21ceuck"
"21CG-2F"
"21CG-5F"
"21CG-5F"select * from A order by a
数据就变成了
"21c_tut"
"21cadse"
"21c-buk"
"21ceuck"
"21CG-2F"
"21CG-2F"
"21CG-2F"
"21CG-5F"
"21CG-5F"
"21CG-5F"
"21CG-5F"
"21CG-5F"
"21CG-5F"
"21CG-5F"
"21c-gij"
"21cg-pc"
"21cg-pc"
"21cg-pc"
"21CG-PR"数据乱套了。怎么回事？
比如，21c- 开头的数据应该在一起才对，21CG- 开头的数据应该在一起才对啊，怎么全给分开了？