This Access tutorial explains how to use UNION and UNION ALL in Access Query.
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UNION and UNION ALL in Access
UNION and UNION ALL are used to combine two Query results vertically into one Query, therefore both Queries require to have the same number of fields and same data types.
When two Queries are combined, there could be rows of record that are exactly the same (duplicates). UNION removes all duplicates while UNION does not remove an...
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