Viewing the Join report

The Join report provides you the details of joins between all the tables in a database.

To view the join report, click Reports > Join Report. You can change the database from the dropdown list to view the join diagram for that database.

You can switch between the databases using the Database dropdown menu.

To refine your search based on time, select the time period from the dropdown. After you select the time period, the corresponding “to” and “from” dates representing the selection are displayed along with the time zone. The time zone that is displayed is that of the DAS server.

You can further refine your join diagram using the following join algorithms:

  • Join
  • Hash Join
  • Merge Join
  • Lateral View Join
  • Sorted Merge

The diagram gets refreshed based on your selection.

If you hover over a particular column, then all the joins with the selected column are highlighted. If you hover over a particular connection line, then the number of times the two columns were joined (also known as the join count) is displayed. The join count that is displayed is for the time period that you select.

For every table present on the Join report, DAS displays the database in which that table belongs. If you select a particular database from the dropdown menu, then the Join report predominantly displays all the joins originating from the tables within the selected database to the tables belonging to other databases.