Do you have extra quotations when it's in the data item? You may know this already, but I'll explain just in case.
If you put the Query into the SQL input of the Get Collection action, it has to have quotations around it like "SELECT * FROM tblTable", but if you put it in a data item it should not have the quotes around it but instead should be like SELECT * FROM tblTable.
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Dave Morris
3Ci @ Southern Company
Atlanta, GA
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Dave Morris, 3Ci at Southern Company