It's got nothing to do with the log records as full backups do not interfere with the log chain. EVER.

The DB on the secondary is read-only. A...

Functions need the schema name.
Also check that you aren't somehow in compat mode 80 or  lower.

The code as posted parses fine for me, can't run as I...

A .trc file is a binary file, so you should expect to get garbage when you open it in a text editor.

What are you trying to do?

Never encrypt passwords. Salted hash, then the app hashes (with the same salt) and you compare the hashes.

Please note: 8 year old thread.

You'll need to join to the table [Test1]. You can't just dump a partial select inside a function where a column or value is required and expect it to...

IN vs EXISTS: https://sqlinthewild.co.za/index.php/2009/08/17/exists-vs-in/
NOT IN vs NOT EXISTS (beware the behaviour difference with NULLs) https://sqlinthewild.co.za/index.php/2010/02/18/not-exists-vs-not-in/

Nope. Temp tables are part of user transactions, and if there's a rollback any operations against them within the transaction will be rolled back. Table variables are the only thing...