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Power Database Fields is a Jira app which enables you to associate a value retrieved retrieve information from an external database to and display it as a value in a ticket field in Jira.
You can execute any types of queries to the database. When data is retrieved, you select it from a set of results as a select list or autocomplete box. Also, each database custom field can have one or more child database custom fields associated, whose values are filled automatically when you select a value is selected for a valuefor the database custom field.
Starting with version 1.1 for JIRA Jira 4.x X and from 2.1 for JIRA Jira 5.xX, the app also provides a new custom field type: Data Table Custom Field that displays information from a configured data source ( a database or a SIL script ) in a tabular fashion.
From Starting with version 1.1.4 / 2.1.4 you can select multiple values from database in the select list, as well as in autocomplete (Jira style).