wpdb updating record in wordpress with json adds extra array elements
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This is killing me - I keep getting magical array elements added to my updated array in WP.

For example if my query is (var_dumped below):

    string(70) "UPDATE wp_mytable SET already_played = '[9]' WHERE user_id = '1'

the already_played cell shows:

    [9,7]

what the hell is going on? Like i say, I var_dump the query and I'm positive its only running once... am I missing something very obvious here? Its set as MEDIUMTEXT.