At the moment Field("a") ** 2 will produce an incorrect SQL for MSSQL: POW("a",2). The POW function in MSSQL is called POWER.

I discovered it while working on a PR in tortoise-orm. Here's related line https://github.com/tortoise/tortoise-orm/pull/1761/files#diff-aa57560853f73b4713b47a1ae27f28c76a227216db2eb068e32649322876ae94R209