Much is made (and easily able to be found on the internet) about how you do not need to use where rtrim(columnname) = 'value' in sql server, because it automatically considers a value with or without trailing spaces to be the same.
However I've had a hard time finding info about LEADING spaces. What if (for whatever reason) our data warehouse has leading spaces on certain varchar / char type of fields and we need to have where clauses - do we still need where ltrim() ? I'm trying to avoid this big performance hit by researching out other options. Thank You
Leading spaces are never ignored in comparisons of any text based data type. If you are comparing the equality of text columns, the best option is to validate your values on data entry to make sure that text with unwanted spaces in front is not allowed. For example if your database is expecting a user to type something from a list of possible values that your database application is expecting, do not allow your user interfaces to let users enter the text free-form, force them to enter one of the explicit valid values. If you need the user to be able to enter free-form text but never want leading spaces, then strip them on the insert. Normalizing your database should prevent a lot of these types of issues.