KDB+ Case insensitive like query

Question

SELECT * FROM MarketTable WHERE customer LIKE "ABC"

This returns only ABC. I want this to return ABC, aBC, abc, etc.

Is there something close to ILIKE in kDB+?

Even functions like lower or tolowercase would help, but I do not think these are available. As in java we have string.tolowercase.

Answer 1

q)t:([] b:1 2 3; a:("abC";"aBc";"AbC"))
q)t
b a
-------
1 "abC"
2 "aBc"
3 "AbC"

q)select from t where upper[a] like "ABC"
b a
-------
1 "abC"
2 "aBc"
3 "AbC"

q)select from t where lower[a] like "abc"
b a
-------
1 "abC"
2 "aBc"
3 "AbC"

However this way the conversion has to happen on each query. Faster to store the column in the format that it will be queried.