Troubleshooting PDTs Stay organized with collections Save and categorize content based on your preferences.
This guide helps you troubleshoot PDTs on your Looker instance. To get started, go to the section that best describes your issue:
PDTs are failing to build
If one or more PDTs are failing to build, check the steps in this section. (If, instead, PDTs are building too frequently, check thePDTs are building too frequently section.)
Use the following decision tree to begin troubleshooting PDTs that are failing to build:
Manually rebuild the PDT
First, test if you can successfully build or rebuild the PDT manually. If this attempt fails,check the build failure error message for more information.
If you can successfully build your PDTs manually, then check the persistence strategy.
Check connection settings
If all PDTs across a single connection are failing to build, check your connection settings. Insufficient scratch schema privileges are a common reason for build failures. Double-check that thescratch schema has been set up correctly. If the scratch schema has been changed recently, first try updating theConnection settings.
If you can successfully build your PDTs manually, and your connection settings are set up correctly, then there is likely anissue with the PDT regenerator on your instance. Reach out toSupport to troubleshoot this edge case.
PDTs are building too frequently
If one or more PDTs are building too frequently, follow the steps in this section.
Use the following decision tree to begin troubleshooting PDTs that are building too frequently:
Too many PDTs in scratch schema
If several copies of a single PDT are clogging up your scratch schema, then there is likely anissue with the PDT reaper (the process that automatically removes old PDTs) on your instance. Reach out toSupport to troubleshoot this edge case.
Check the build reason in the PDT Activity dashboard
Check thePDT Activity dashboard for more information. In particular, check theBuild reason for the PDT that is building too frequently. Some common build reasons include the following:
- The table isn't in the scratch schema: The PDT was built because no version of this PDT was found in the scratch schema. Try checking your connection settings and changing your scratch schema. If you have multiple Looker instances, such as a production instance and a QA instance, make sure to set different scratch schemas for each instance to avoid PDT management conflicts.
- Manual rebuild: The PDT was manually rebuilt by a user. Check for the user's ID and see if that user is manually triggering too many PDT builds.
- Dependent PDT builds: This PDT was built because another PDT depends on it. Find the dependent PDT and check its persistence strategy.
Final review and support
If you're still having trouble with your PDTs, review the troubleshooting steps on this page. If you're still unable to resolve the issue,contact Support.
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Last updated 2025-10-02 UTC.