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You can see some of them in action from SQL built-in console in Jira: Click on the Examples link, then on the Tricks link and Run it.

Native Functions

SQL+JQL is really H2 therefore you can use almost all the H2 functions described in the product documentation:

http://www.h2database.com/html/functions.html

Custom Functions

SQL+JQL also supports some built-in functions to deal with specific Jira data and formats.

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