Padding and inconsistent case can stop two keys from matching even when they refer to the same person. Trim removes whitespace at the ends of text. Data Cleansing applies selected rules across selected fields, while Formula lets you express a particular rule for a single output. Choose the fields deliberately so a cleanup intended for email doesn't alter a free-form note.
Contains tests whether text includes a substring. Left returns a requested number of characters from the start, and Regex_Replace can replace a pattern. These functions serve different jobs. Replacing every hyphen in an identifier is different from taking its prefix. Decide how nulls should behave before applying a text expression, and keep the raw source when an audit needs to explain the transformation.