fix: Skip explain plans which lookup individual records and return no rows #5203
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fix: Skip explain plans which lookup individual records and return no rows #5203
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| msgBlock, _, _, err := jsonparser.Get(redactedByteExplainPlanJSON, "query_block", "message") | ||
| if err == nil { |
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Just checking: if err != nil are we happy not doing anything and moving on?
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I think yes. The most likely scenario is that it did not find the requested json node.
That said, this is probably not the most deterministic way to handle it. I should check for error, and empty string separately.
cristiangreco
approved these changes
Jan 8, 2026
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Brief description of Pull Request
In MySQL, the query we're executing for explain plans gets an updated concrete query in
performance_schemaperiodically.For queries which look up a single row, by a primary key id, for a record which does not exist, no explain plan is created.
This created situations where a customer would sometimes see an explain plan, and sometimes not for a given query.
This PR simply refrains from logging the empty explain plan, such that the dbo11y UI should only find explain plan records with content for a given query.
Issue(s) fixed by this Pull Request
Fixes #4987
Notes to the Reviewer
This just debug logs the fact that we're skipping, and does not communicate with the user or the dbo11y UI in any way.
In the future, I'd like to add some additional telemetry which a user can opt-in to with their alloy config to have more visibility to the frequency with which individual queries are dropped for the various reasons.
PR Checklist
BEGIN_COMMIT_OVERRIDE
fix(database_observability): Skip explain plans which lookup individual records and return no rows (#5203)
END_COMMIT_OVERRIDE