Prevent illegal column names with PHP for MySQL

[ginanjarfm]

Great thanks for your works. Unfortunately, to prevent illegal column name I should update the codes. You can merge this if you don't mind. Thanks.

[blag001]

Duplicate of #71 / #70

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As said there : #70 (comment)
It'll be a good idea to make this change for the whole project and not making 10 pull request to patch one by one every query (which is the best way to miss one or more and go in funny debugging party...)

If you've got some time, it'll help us ;-)

[worthy7]

yay.

[MartynasJanu]

This line must be fixed also:

$orderClause = " ORDER BY ". $columns[(int)$orderValue['column']]['data'] . " " . $orderValue['dir'];