< Marvin> i am running prefect onprem with postgres with con Prefect Community #marvin-in-the-wild

Well, it appears getting the version info directly is a bit of a struggle. Let's try another approach. I will search for potential issues related to Prefect UI not showing up after installation using both the 2.x and 3.x documentation search tools. This way, we might uncover useful troubleshooting steps directly. Let me do that. So, you've installed everything but the UI decided to pull a Houdini. Let's dig into some steps to help you troubleshoot this mess. 1. Confirm Prefect Version: Ensure you are running the latest version. Run:

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pip install --upgrade prefect

2. Check Prefect Services: Ensure all services are up and running. You can use:

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prefect dev start

3. Development Mode: For UI development, make sure you have npm installed and try starting the development UI:

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prefect dev ui

4. Browser Troubleshooting: - Hard refresh (Cmd+Shift+R) - Try a different browser (Chrome, Edge, Firefox, Safari) - Clear recent browser history/cookies 5. Inspect Prefect Logs: Check the logs for any errors that might indicate why the UI isn't showing. 6. Email Prefect Support: If all else fails, email help@prefect.io with specific details about your setup. For detailed guidance, check the official troubleshooting docs: - Troubleshooting Guide - Prefect Cloud Troubleshooting Good luck with that. Doesn't it all just sound thrilling?

Nate

09/03/2024, 1:01 PM

hi @seto -- are you using something like

--host 0.0.0.0

for

prefect server start

seto

09/03/2024, 1:03 PM

Hi @Nate, I'm not.. Just run prefect rebuild sql lite to postgres then run prefect server start, am i wrong?

Nate

09/03/2024, 1:04 PM

oh sorry, i thought you meant you were running the server in a container as well can you show the logs that come from

prefect server start

or otherwise explain how you're running the server?

seto

09/03/2024, 1:12 PM

Ya later i will show you the logs, but I'm afk now. What I've done are: 1. Create dockerfile to install prefect, and postgres is on the host 2. Build image from no. 1 then docker run with command prefect server migrate and prefect server start

👍 1

seto

09/04/2024, 3:13 AM

@Nate whole prefect server is running well now, just change some prefect server command related the host and server ip's

Nate

09/04/2024, 3:39 AM

catjam

seto

09/20/2024, 1:44 PM

Hi @Marvin i got this error when i restoring prefect container

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tables can have at most 1600 columns
[SQL: ALTER TABLE deployment ADD COLUMN description TEXT]

Marvin

09/20/2024, 1:44 PM

The error you're encountering, "tables can have at most 1600 columns [SQL: ALTER TABLE deployment ADD COLUMN description TEXT]", is related to a PostgreSQL limitation. It seems the

deployment

table has reached its maximum column limit, preventing further alterations. Here's what you can do: 1. Check for Existing Columns: Query your database to understand the current schema, especially the

deployment

table, to see why it's so wide.

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SELECT column_name
    FROM information_schema.columns
    WHERE table_name = 'deployment';

2. Database Clean-Up: If feasible, review and clean up unused or deprecated columns. 3. Revisiting Table Design: This issue might indicate a need to revisit the schema design, possibly normalizing the table. For more details, you can refer to these resources: - Prefect 2.x Integrations and Model Guides - Contribution and Database Definition You can also check up with Prefect's support or community for further advice on managing schema updates. Good luck! Feel free to ask if you need more help.

seto

09/20/2024, 1:47 PM

@Marvin just 11 columns from record of deployment table

Marvin

09/20/2024, 1:47 PM

If you only have 11 rows in your

deployment

table yet you're hitting the column limit, there might be a historical accumulation of columns over time from various upgrades or alterations. Here are more targeted steps to troubleshoot and resolve the issue: 1. Database Schema Review: Run the following SQL to inspect the

deployment

table structure:

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sql
   SELECT column_name, data_type
   FROM information_schema.columns
   WHERE table_name = 'deployment';

2. Prefect Schema Management: Inspect Prefect's migration history to see if there have been multiple alterations adding excessive columns. Look for unusual patterns or repeated columns. 3. Manually Drop Unnecessary Columns: If you spot any columns that are unused or duplicated:

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sql
   ALTER TABLE deployment
   DROP COLUMN your_column_name;

4. Migrate Data (if necessary): If feasible, create a new table with a cleaned-up schema and migrate the data manually. This might involve updating the Prefect's metadata to point to the new table. 5. Review Deployment Code Changes: Check the source code in `orm_models.py` or other relevant files for any unnecessary column additions:

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python
   class ORMFlowRun(ORMRun):
       ...
       # Review additional column definitions
       new_column = Column(String, nullable=True)

Keeping your schema lean and clean helps in avoiding such issues in the future. Feel free to let me know if you encounter any specific stumbling blocks while applying these solutions.

Marvin

09/20/2024, 1:48 PM

If your

deployment

table only has 11 columns but you're running into the "1600 columns" error, it likely means that some previous schema alterations might have left unused column entries which are counted towards the PostgreSQL column limit. Here's a detailed troubleshooting path: 1. Verify Table Columns: Check the columns in your

deployment

table:

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sql
SELECT column_name, data_type
FROM information_schema.columns
WHERE table_name = 'deployment';

2. Examine Schema Migrations: Review Prefect's migration files to see if there were any frequent and possibly redundant alterations made to this table. 3. Altered Columns History: Check the history of schema changes. You can look into the migration versions or database revision history to see what alterations have been applied:

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shell
prefect server database revision --autogenerate -m "<migration name>"

4. Dropping Unused Columns: You can drop columns which no longer serve a purpose:

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sql
ALTER TABLE deployment
DROP COLUMN column_name;

5. Vacuum and Reindex: After removing unused columns, perform a vacuum and reindex:

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sql
VACUUM FULL deployment;
REINDEX TABLE deployment;

6. Schema Design Review: Consider normalizing your table schemas if they consist of too many fields representing different functionalities. If these steps still don't resolve the issue, please share more context or specifics about the changes you've made leading to this problem. This will help in diagnosing the root cause more effectively. You might also consult Prefect's support or raise a GitHub issue explaining the odd column limit behavior you're experiencing. The development team may provide insights or patches to resolve this unique case.

seto

09/20/2024, 1:54 PM

there is nothing tables have 1600 columns

seto

09/20/2024, 2:01 PM

so how @Marvin? there is nothing tables in prefect db have 1600 columns

Marvin

09/20/2024, 2:02 PM

If you are certain that none of the tables in your Prefect database have 1600 columns, yet you still encounter this PostgreSQL error when running migrations, it might be a Prefect-specific issue. Here’s a refined approach to troubleshoot and fix this: 1. Validate Current Schema: Ensure you genuinely have only necessary columns.

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sql
SELECT table_name, COUNT(column_name)
FROM information_schema.columns
WHERE table_schema = 'public'
GROUP BY table_name
ORDER BY COUNT(column_name) DESC;

2. Inspect Migrations: Review migration files. If there's a possibility of redundant migrations causing the schema bloat, inspect Prefect’s alembic revisions and migrations.

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shell
ls -l $(pip show prefect | awk '/^Location: /{print $2}')/alembic/versions/

3. Check for Orphaned Columns: Ensure no hidden or orphaned columns might be contributing to the perceived column count:

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sql
SELECT a.attname, a.atttypid, a.attstattarget, a.attlen, a.attnum, a.attndims, a.attcacheoff, a.atttypmod, a.attbyval, a.attstorage, a.attalign, a.attnotnull, a.atthasdef, a.attisdropped, a.attislocal, a.attinhcount, a.attcollation, a.attidentity, a.attidentityseed, a.attidentityincrement, a.attidentitymax, a.attidentitymin, a.attidentitycycle, a.attgenerated
FROM pg_attribute a
WHERE attrelid = (
    SELECT oid
    FROM pg_class
    WHERE relname = 'deployment'
) AND a.attisdropped IS FALSE;

4. Modify IDENTITY Columns: If identity columns are problematic, redefine them carefully. 5. Prefect Support: - Raise a GitHub Issue: If the problem persists, report it as an issue to the Prefect GitHub repository. Provide detailed context. - Prefect Issues: https://github.com/PrefectHQ/prefect/issues - Community & Support: Engage with Prefect community or support for specific troubleshooting steps. Links for more help: - Prefect Troubleshooting Guide - GitHub Issues Following these steps should help identify and resolve the column limit issue. If you have further details or logs, sharing them can refine diagnostics.

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