We’re starting a blog series dedicated to helping you improve the performance of Tableau in your environment. It all starts with the Best Practice Analyzer from Workbook Tools for Tableau. This feature lets you know exactly how you can improve your Tableau workbooks to run faster and smoother.
Each post in the series is related to specific performance issues that are flagged by the Best Practice Analyzer. If you don’t have it yet, get it. You can also check out more guidelines found on our Tableau Performance Checklist.
The Flag
You’ve just been notified by Best Practice Analyzer that your dashboard has been flagged due to a calculated field being used that is greater than 500 characters in length. It can be tough to stay under 500 characters sometimes, but this length can cause slow performance and increase the time a view takes to render.
Points to Consider
When creating such lengthy calculated fields, consider the logic behind your calculation. Is this something that could be added into your data to begin with? Are you trying to accomplish multiple things with this calculated field rather than separating it out into multiple fields? Are you experiencing slow performance currently? If so, consider breaking your calculations out into multiple fields or cutting out any additions that aren’t absolutely necessary.
This flag is just a suggestion, but be sure to take note. This could be an issue resulting is a loss of performance, but in most cases, it’s an easy fix.
An Example
In the example below, a goal is being set by Year. Due to the other fields involved to set the goal, the calculation become very drawn out. Answering the questions above helps guide us to possible solutions. If, however, the calculated field is your only option, this field is a good example of breaking into 2014 and 2015 goals rather than ALL together.
Curious about other Tableau workbook performance best practices? We have a growing list of posts to help you out. Here are the topics we’ve covered so far:
- Custom SQL Connections
- Automatic Dashboard Sizing
- Context Filters
- Reduce Number of Dashboard Worksheets
- Conditional Filter Logic
- Images & Shapes
- Word Clouds
- Mixed Data Connections
- Quick Filter Cardinality
- Relevant Value Filters
- Row-Level Parameters
- Table Calculation in Level of Detail
- Teradata Initial SQL
- Unused Data Sources
- Blending Calculations
- Unused Columns