What about the about ANSI_QUOTES note on https://dev.mysql.com/doc/c-api/9.1/en/mysql-real-escape-string-quote.html ? Could this cause a regression for ANSI_QUOTES with double quoted characters?

Please add any info on the usecase for this and why it would be safer etc.

So for this looks like an ok change to me.

Please add any info on the usecase for this and why it would be safer etc.

If you run t/17quote.t on the previous version of the code, you can see that NO_BACKSLASH_ESCAPES causes placeholder replacement to produce invalid query syntax (effectively the ? placeholder is replaced by a single ' because mysql_real_escape_string returns -1 and rewinds the pointer).

ok 20 - NO_BACKSLASH_ESCAPES foo
DBD::mysql::db selectrow_array failed: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''' at line 1 at t/17quote.t line 34.
DBD::mysql::db selectrow_array failed: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''' at line 1 at t/17quote.t line 34.
# Looks like your test exited with 255 just after 20.

What about the about ANSI_QUOTES note on https://dev.mysql.com/doc/c-api/9.1/en/mysql-real-escape-string-quote.html ? Could this cause a regression for ANSI_QUOTES with double quoted characters?

In this context, we're never processing a double-quoted string. We've added single quotes ourselves for quoting purposes.