Try using Cross datasource joins , you will be able to do what you want using this feature. for more details please refer As requested, you can filter across data sources in Tableau 10 | Tableau Software
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Create a join between SQL1 and SQL2 in the custom sql , and there after you can put the filter as usual , without any extra effort.
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I am using Tableau 9.3 which I think does not have this option?
Is there any other alternate solution?
Is there a way to achieve this through - Data>Edit Relationships option in Tableau.?
You can also do Data blending and achieve it. But, there are few limitations with this approach. You can check in the knowledge base for more details.
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