Tables/Views could not be fetched

[Imran980]

I am getting the subject error in GCP MySQL that is on every database I have in the cloud instance. It gives more information in the message area as below. This error is on multiple views.

• Error loading schema content.
  Error Code: 1356 View 'databasename.my_view_01' references invalid table(s) or column(s) or function(s) or definer/invoker of view lack rights to use them

This I have checked all the views many times and there is not such invalid table or column, and the views are working fine but still the error appears.

When I recreate the views the error goes away for few days or even weeks but then reappears.

• I am using Workbench and I have tried other tools too to resolve this issue.
• I have removed/added/changed definer but no luck.
• I have tried different users in addition to root(superuser).
• All the underlying tables are good and posses the columns referenced by the defective views.

Any help will be appreciated!

[ms4446]

Intermittent view errors in Cloud SQL MySQL can stem from several causes. Caching issues may arise from inconsistencies in MySQL’s metadata cache, which can be temporarily resolved by flushing the cache, though the problem might recur. Replication delays or inconsistencies between master and replica instances could also lead to these errors. Even after adjusting the definer, permission issues related to the user who created the views might persist, so it’s important to ensure appropriate permissions are maintained. Additionally, any DDL operations (e.g., ALTER TABLE) on underlying tables can temporarily invalidate views. Here are steps you can take to troubleshoot:

View Definitions:

• Check Accuracy: Ensure all table and column references in the view are correct and that the logic of the view is accurate.

• Review Changes: Make sure that any recent changes to the underlying tables, like modifications to the schema, haven’t affected the views.

Table and Column Existence:

• Confirm Availability: Verify that all tables and columns referenced in the views still exist and are accessible.

• Match Data Types: Ensure the data types in the views match those in the underlying tables.

Privileges:

• Check Permissions: Verify that the user or role associated with the view has the necessary access privileges.

• Look for Restrictions: Check if there are any database or instance-level settings that might be limiting access.

View Definer:

• Verify Permissions: Ensure that the user who created the view (the definer) has sufficient permissions to run the view.

• Modify if Needed: If necessary, update the view’s definer using the DEFINER clause to ensure proper access.

Underlying Data Changes:

• Assess Impact: Check if recent changes to data or table structures have affected the view’s functionality.

• Update Views: Modify the view definitions if needed to reflect any changes in the underlying data.

Schema Integrity:

• Check for Corruption: Use the CHECK TABLE command on the underlying tables to ensure they are not corrupted.

• Repair if Needed: If you find corruption, use REPAIR TABLE to fix the tables (note that this doesn’t apply to views directly).

System Activity:

• Monitor Resources: Use Cloud Monitoring to keep an eye on resource usage and spot any potential issues.

• Watch for Anomalies: Look for unusual entries in the system logs that could help identify the root cause of the error.

[Imran980]

Thank you for the detailed check list. I did verify and checked all the helptips above but the issue remains there. Also its not the first time I am seeing this error. Last time I had this error I just recreated those views and the issue was gone, but reappeared after a month or so. This time I again recreated one of the error causing views and its not throwing error now but the others do. However, I am pretty sure this one will too appear again soon.

[ms4446]

Given the recurring nature of this issue, it's clear that a more lasting solution is needed. One temporary fix is to automate the regular rebuilding of the views. By setting up a job to drop and recreate the views at scheduled intervals, you can help prevent these errors from disrupting your work, even though it doesn't solve the root cause.

Another option is to upgrade to the latest MySQL version if you haven't done so already. Newer versions often come with bug fixes that might resolve this issue. If the problem persists across different versions, reaching out to Google Cloud Platform support could be helpful, as they might offer deeper insights or specific patches for this issue.

At the same time, setting up automated monitoring to catch these errors as soon as they occur can help you respond more quickly. Alerts can minimize the impact by notifying you immediately, allowing for fast action.

Finally, you might want to consider changes to your database setup. Simplifying the views, restructuring your schema, or even using materialized views could lead to more consistent performance. Although these options involve more effort, they might provide a more permanent fix to this ongoing problem.

[fik2024]

By all of the above comments, It seems like this the bug related to mysql? I am facing the same issue and check for all the precauions. but issue remains there. Only way to resolve the issue is by re-creating the view. but it can re-occur any time.