以下是引用sdta在2021-7-26 16:42:18的发言：

create cursor b1 (m1 c(3),m2 c(3))
insert into b1 values ("ab","bb")
insert into b1 values ("a","b")
insert into b1 values ("bb","a")
insert into b1 values ("","bb")
insert into b1 values ("bc","")
insert into b1 values ("c","ab")
LOCAL aa[FCOUNT()]
aa = ""
SCAN
    FOR lnj = 1 TO FCOUNT()
        b1 = ALLTRIM(EVALUATE(FIELD(lnj)))
        IF LEN(b1) > 0
            FOR lnk = 1 TO LEN(b1)
                b2 = SUBSTR(b1, lnk, 1)
                IF NOT b2$aa[lnj]
                    aa[lnj] = aa[lnj] + b2
                ENDIF
            ENDFOR
        ENDIF
    ENDFOR
ENDSCAN
LIST MEMORY LIKE aa

以下是引用fdqzy在2021-7-26 17:09:08的发言：


谢谢！
    好像版主是统计的所有列，不是单列m1列或m2列?

以下是引用吹水佬在2021-7-27 11:41:59的发言：

如果字符相对固定（假设数据只是小写字母），算法可以简化一下（减法）：
create cursor b1 (m1 c(3),m2 c(3))
insert into b1 values ("ab","bb")
insert into b1 values ("ax","b")
insert into b1 values ("bb","a")
insert into b1 values ("z","bb")
insert into b1 values ("bc","")
insert into b1 values ("cy","ab")
cs = "abcdefghijklmnopqrstuvwxyz"
? "m1:", fun("m1")
? "m2:", fun("m2")
RETURN

FUNCTION fun(cf)
    s = cs
    SCAN
        s  = CHRTRAN(s,ALLTRIM(EVALUATE(cf)),"")
    ENDSCAN
    RETURN CHRTRAN(cs,s,"")
ENDFUNC