Does single-character wildcard not supported in datatable.select ()

28337755

datatable.Select ("col like 'a_'")
Cannot return value

若水淡淡

datatable.Select("col like'%a_%'")

shenmue024

% And * can. _No.

28337755

How do single characters match

shenmue024

How do single characters match
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Can't find the answer.

28337755

ok, thanks!