Description:
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Perhaps PDO could have a settable readonly attribute. That way scripts which only require readonly access would be that much more secure. Of course, this could be implemented as a second database user which only has readonly access but some people may be on shared hosts which only give one database user.  There is no substitute for properly escaping all user input but this could provide one more layer of protection.

Reproduce code:
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Expected result:
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Actual result:
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