Listing IDs that match values in two columns of a table
SELECT DISTINCT abbreviations.*
FROM attachments
JOIN abbreviations ON abbreviations.Abbreviation IN (attachments.`To`, attachments.`From`)
WHERE attachments.RowID IN ('2019.06.05',
                            '2019.06.11',
                            '2019.06.12',
                            '2019.06.15',
                            '2019.06.22');


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