The SQL Query Tester
is a place where one can write the first draft of SQL expressions that will later be used in the Create Entity widow when the type SQL Query is selected. Through this means you can ensure there are no mistakes in the query and it works as expected before using it to define a rule for the data mapping.
It is essential to choose the correct source data set before executing your query.
If there are no source data options in the drop down window, try going to the data sources window and then returning to this window.
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