How Query Store And Plan Guides Interact

Grant Fritchey shows that query metadata gets a little weird when you have a plan guide trying to use one particular query and Query Store is forcing a different plan:

If we rerun the query and then take a look at the first operator in the execution plan, we can see that the Plan Guide is in use… and that the query hash has changed. It no longer matches the original query. Now it matches the query that included the query hint. This actually makes perfect sense. The Plan Guide is basically changing the query from the first example above, into the second.

Now, what happens when we toss in the Query Store

The query behavior is exactly what you want, but some of the metadata is no longer correct.

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