How many characters does the * wildcard represent?

The wildcard symbol * represents many characters in various programming and data querying contexts, such as SQL and Alteryx. This symbol allows users to match any number of characters, making it incredibly useful for searching and filtering datasets where the exact number of characters in a string is not known or isn’t essential. For instance, if you were searching for filenames or text entries that start with a specific phrase but end with varying amount of characters, using the * would return all the possible matches that fit the initial criteria.

In contrast, the other options proposed do not accurately describe the function of the * wildcard: it does not represent only one character, exactly two characters, or none at all. Thus, it's clear that the * wildcard is intended to match a variable length of characters, confirming why the chosen response is the most appropriate.