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So actually, this is quite an easy answer, and doesnt require turning off loads.

In Short, do the following:
Query 1 (Data Pull) - This is main data pull in query. Do as little as needed to the data (normally ensure that all columns are in a data format). Do nothing else.
Query 2 (Data Pull Reference) - Create a reference to the above Datapull, do nothing, but ensure its well labelled. This is what your going to use for further queries

Query 3 (Main Query) In this query, make a reference to the above Query 2 and then do all your maniupulation. Any other queries you need to bring in, ensure you have done the the other two queries, so all  you are bringing in is a referenced query.

Works a like a dream.....