Wrong CD read in by old database

I believe the answer is:

cardindex

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'old database' is the definition.
The definition suggests a singular noun which matches the answer.

'wrong cd read in by' is the wordplay.
'wrong' is an anagram indicator.
'by' becomes 'x' (multiplication sign).
'cd'+'read'+'in'='cdreadin'
'cdreadin' with letters rearranged gives 'cardinde'.
'cardinde'+'x'='CARD-INDEX'

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I've seen this clue in The Daily Mail.

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