WARN: 4 statements have not been closed before the closure of the managed connection

[YuriRibeiro]

I’m having trouble connecting to a postgres db
connection node works but the query reader and table reader doesnt

when i try to fetch metadata i get this warn on the console:
WARN DB Query Reader 7:6 4 statements have not been closed before the closure of the managed connection.

any ideas?
thx in advance guys !
knime version is 5.11

[takbb]

Hi @YuriRibeiro , use /* and */ to comment out lines in the DB Query Reader node, instead of -- if you are going to use Evaluate because the whole statement gets concatenated into a single long string and so everything after the -- (which includes subsequent lines that you have entered and the additional end of the wrapper select statement added by “evaluate”), becomes commented out.

e.g.

If you have

Select x, y, z from mytable

-- a comment

This becomes
Select * from (Select x, y, z from mytable -- a comment )

so that final additional ) is no longer part of the executable sql.

[YuriRibeiro]

Thx but it seems that the comments are not the problem
the error occurs when i try to evaluate
the warning saing “4 statements have not been…” happens when i try to fetch metadata

[takbb]

Hi @YuriRibeiro , a pity that didn’t resolve it but certainly the commenting can cause problems.

Anyway, ignoring the meta fetch for a moment, what happens if you have a simple query such as

select now()

And press the evaluate button? Does it get a return from the database?

[YuriRibeiro]

hi @takbb
surprisingly it did returned something!
although i dont think i’m contacting the database

[takbb]

That will only return a date/time if there is a database on the other end. You could also try

SELECT nspname
FROM pg_catalog.pg_namespace

Which will either return a result or an error from the database. It should prove you have a connection at least!

What if you try to fetch the metadata now. Does it still give the previous error?

[YuriRibeiro]

@takbb
it did returned the values showing that the schema ‘public’ indeed exists, but my query still doesnt work. it is returning the same errors saing the table doesnt exists.
I used an app called heidi to test the connection and the query, both working fine.
fetching metadata is returning the same warn message =/

[takbb]

So this is progress of sorts…

Try the following query

SELECT * FROM information_schema.tables 
WHERE table_schema = 'public'

and see if that returns results

then try this query:

SELECT tablename FROM pg_tables 
WHERE schemaname = 'public'

Finally, if you go back to your original query, and you ignore the “metadata” button, and also ignore the “Evaluate” button, and so the query is as per your screenshot:

then click Apply and OK, what happens if you try executing the DB Query Reader node. Do you get an error, or does the query itself return results?

[YuriRibeiro]

@takbb my friend
your queries returned empty tables witch gave me info to confront my IT
they gave me access to an empty database and configured a diferent one on heidi
its all set now,
metadata is working fine

again, thx so much!
i learned a lot with ur suggestions

[takbb]

Phew! Glad you got it sorted @YuriRibeiro , and thanks for marking the post as the solution.