Custom and union tables
In order to customize the name and number of columns of a data table, you can create custom tables based on specific queries. Change the names of the columns or remove the ones you don't need to define a table that best fits your needs.
After creating a custom table, you can merge its contents with events from other tables and create a union table. Columns that are present in all the tables will be automatically merged, and you can include additional columns from the selected tables to the final union. Note that union tables are always the result of merging the data of a previously created custom table with events from other queries.
Both custom and union tables can be accessed in Data Search → Finder. The tags corresponding to custom and union tables always start with my.synthesis or my.blend, so you can easily identify them in the finder.
You can define both custom and union tables opening the required data table and going to Additional Tools → Custom tables. Learn how to create and manage them in the following articles: