for same query_text refresh just execution once

[gaecoli]

What type of PR is this?

• Refactor
• Feature
• Bug Fix
• New Query Runner (Data Source)
• New Alert Destination
• Other

Description

How is this tested?

• Unit tests (pytest, jest)
• E2E Tests (Cypress)
• Manually
• N/A

Related Tickets & Documents

Mobile & Desktop Screenshots/Recordings (if there are UI changes)

[gaecoli]

This PR introduces a mechanism to prevent duplicate execution of the same SQL query in a distributed environment. By implementing a distributed locking mechanism using Redis, we ensure that only one process or thread can execute a specific SQL query at a given time, avoiding unnecessary load on the database and ensuring consistent query results.

[arikfr]

@gaecoli I did this change to match changes on master. Not sure why it shows up in diff, but it's fine.

[arikfr]

@gaecoli I wonder if we really need this? I mean the chance of the exact same query being executed at the same time are usually low vs. the complexity and potential issues this might add.

Do you have this happen frequently?

[gaecoli]

@gaecoli I wonder if we really need this? I mean the chance of the exact same query being executed at the same time are usually low vs. the complexity and potential issues this might add.

Do you have this happen frequently?

OK, i will consider that! Thank you! @arikfr

[gaecoli]

@gaecoli I wonder if we really need this? I mean the chance of the exact same query being executed at the same time are usually low vs. the complexity and potential issues this might add.

Do you have this happen frequently?

When i add the same query at a dashboard, the query has lot of visualizations, table, chart..., when i add this at a dashboard, i refresh dashboard, the same query text will all execution many times in query engine (Presto, MySQL, doris...).

At my company, 1000+ people maybe refresh same dashboard, so you know what i say.

[eradman]

Unfortunately this does happen more often than I would have guessed. Any time multiple visualizations of the same query is included on a dashboard there is a high probability of duplicate queries

SELECT regexp_matches(query, 'Query Hash: [a-z0-9]+') FROM pg_stat_activity WHERE state='active';

\watch 1
...
                  regexp_matches
--------------------------------------------------
 {"Query Hash: 5aa874345926f2b18ecf197d3200a602"}
 {"Query Hash: 5aa874345926f2b18ecf197d3200a602"}
(2 rows)

For very long queries (not uncommon for my users!) this will cause unnecessary load.

[arikfr]

Maybe the right thing will be to make dashboards refreshes smarter and reuse the same query invocation for different visualizations that depend on it? I think it will be more robust and address the core issue instead of trying to address it in an indirect way.

[eradman]

Maybe the right thing will be to make dashboards refreshes smarter and reuse the same query invocation for different visualizations that depend on it

That seems like a good approach, unless this also becomes complex. My guess is that a dashboard is the only API user that would normally hit this race condition.

[gaecoli]

Maybe the right thing will be to make dashboards refreshes smarter and reuse the same query invocation for different visualizations that depend on it? I think it will be more robust and address the core issue instead of trying to address it in an indirect way.

This is a good approach, but I think such a change would make the code more complex.

[eradman]

Tested this change manually, it does seem to work. Also I see the log messages

server-1 | [2025-02-07 13:56:32,160][PID:19][INFO][redash.utils.locks] Lock released successfully, lock_name=[lock:query_hash_job:1:d6338e9508dd103771b69483fb17d4a5], identifier=[73683a39-6aea-4f29-b0d3-02e4c0385a0b]

[gaecoli]

Tested this change manually, it does seem to work. Also I see the log messages

server-1 | [2025-02-07 13:56:32,160][PID:19][INFO][redash.utils.locks] Lock released successfully, lock_name=[lock:query_hash_job:1:d6338e9508dd103771b69483fb17d4a5], identifier=[73683a39-6aea-4f29-b0d3-02e4c0385a0b]

Yes, because it's work well at my company's Redash!