近来想检查一下表中某个字段的填写规范，结果十分混乱，我想使用使用SQL语句如何判断某字段是以字母开头而不是汉字开头 方法：1.
近来想检查一下表中某个字段的填写规范，结果十分混乱，我想使用使用SQL语句如何判断某字段是以字母开头而不是汉字开头 方法：
1.if lengthb(substr("",1,1))==2 then
汉字
elseif lengthb(substr("",1,1))==1 then
字母
end if
2.利用 not like '\%' 返回的是以字母开头的记录，
利用 like '\%' 返回的是以汉字开头的.
原理：asciistr()函数对非ASCII代码，会转换成二进制，且前面加\ ;所以asciistr(acolumn) 如果是汉字;转换出来的会有 \
例如：select asciistr('china') from dual;
china
所以可以很容易区分汉字和字符了
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