Anyway, my question: can I use placeholders in case I don't want to change the value of a column, without obtaining the old value from the record first?
No. The purpose of placeholders is to prevent injection of sql code (basically save you the trouble of calling quote).

In reply to Re: How to get a placeholder to keep the current column value? by Anonymous Monk
in thread How to get a placeholder to keep the current column value? by liz

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