The application provides you with 3 ways of building queries:
Visual query builder
Query Library
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For advanced users of SQL language, it might be more comfortable to use our Console, where you have an opportunity to write your own query. More information about the specification of SQL used in the console you can find here (put a link on technical documentation about SQL version that we use).
If it's more comfortable for you to build a query in a more visual way, where you can see all relative tables of Data from your Jira - Visual Query Builder will help you to construct it in an easy and fast way.
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