You can create DB indices for transformed versions of columns

You can create DB indices for transformed versions of columns

⚡️ Database Tip

Most developers are puzzled that indexes are not used for e.g. WHERE LOWER(email) = ?. But contrary to common belief, an index can be created for these cases! It's called a function-based index and is supported by MySQL and PostgreSQL.

https://sqlfordevs.io/tips/function-based-index

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