This section will cover some basics of database tuning and ways to work efficiently with large data sources. Since the topic is more focused on data sources than on Tableau, no exercises are included.
If you are connecting to large data sources and are experiencing performance problems, a conversation with a Database Administrator (DBA) may be beneficial. Clear communication coupled with a small amount of database work could dramatically improve performance. The conversation should include database tuning points such as explicitly defining primary and foreign keys, defining columns as NOT NULL, and indexing. Each point will be discussed here.
Primary and foreign keys are essential for joining tables. A primary key comprises one or more columns in a table. The primary key should be unique for every row. Joining on a non-unique, row-level key may lead to erroneous results as explored in the exercise titled A data...