比较q kdb中表的两个字符串列的值

Question

我们有一张桌子：

q)t:([] a:("abc";"def";"ghi";"lmn"); b:("abc";"xyz";"ghi";"def"); c:1 2 3 4)
q)t
a     b     c
-------------
"abc" "abc" 1
"def" "xyz" 2
"ghi" "ghi" 3
"lmn" "def" 4

预期输出：逐行匹配 a 列和 b 列并相应更新 mu 列

a     b     c mu
---------------------
"abc" "abc" 1 match
"def" "xyz" 2 unmatch
"ghi" "ghi" 3 match
"lmn" "def" 4 unmatch

当我在查询下运行失败时，输出是

q)select a,b,c, mu:?[any a like/: b; `match; `unmatch] from t
a     b     c mu
---------------------
"abc" "abc" 1 match
"def" "xyz" 2 match // Issue here, since match a value of column a in all value of b
"ghi" "ghi" 3 match
"lmn" "def" 4 unmatch

Answer 1

如果您希望进行逐行匹配，则可以使用 match 运算符 (~) 和 each-both 运算符(')。

 q) update  mu:?[a~'b;`match;`unmatch] from t