The expression must return a value that is a built-in CHAR, VARCHAR, GRAPHIC, VARGRAPHIC, numeric, or datetime data type. If the value is not a CHAR, VARCHAR, GRAPHIC, or VARGRAPHIC data type, it is implicitly cast to VARCHAR before eva luating the function.If from-string-exp contains duplicate characters, the first one found will be used, and the duplicates will be ignored. If to-string-exp is longer than from-string-exp, the surplus characters will be ignored. If to-string-exp is specified, from-string-exp must also be specified.

pad-char-exp

Specifies a single character that will be used to pad to-string-exp if to-string-exp is shorter than from-string-exp. The expression must return a value that is a built-in CHAR, VARCHAR, GRAPHIC, VARGRAPHIC, numeric, or datetime data type. If the value is not a CHAR, VARCHAR, GRAPHIC, or VARGRAPHIC data type, it is implicitly cast to VARCHAR before eva luating the function. The value must have a length attribute of zero or one. If a zero-length string is specified, characters in the from-string-exp with no corresponding character in the to-string-exp are removed from char-string-exp or graphic-string-exp. If a value is not specified a single-byte blank character is assumed.

具体实现语句如下：

1

length(trim(translate(r.ITEM,'','0123456789')))=0

这条sql语句简单说明，当ITEM字段的中包含0~9中的任一数字时，就替换为空字符，当全部为数字时，就全部替换为空字符了，通过trim()函数去空格然后length函数一测量，连渣都不剩了.为0.此时就可以判定为全部是数字字符了。