Connection to table with Database Table selector

Hello Community! I’m a quite new user in KNIME and I have my first doubt/question. It’s related to the connection to the database using node: “Database Table Selector (legacy)”. I clicked in Configure and I found the table I want to connect by clicking Fetch Data in the window “Database browser” on the left, but I can not connect to that table because I get an error saying that object doesn’t exist. Do you know why? The table is appearing inside the database, it should exists.

Many thanks in advance for your suport.

Riccardo

Hello @Riccardo_st,

and welcome to KNIME Community!

You are using legacy database framework. Is there specific reason why aren’t you using new/current DB framework (those are database nodes without legacy)? If not I suggest you give it a try as it offers more dedicated connectors and functionalities. Here is link to Guide which might be useful:

Br,
Ivan

Hi @ipazin and many thanks for the quickly answer.

I’m using legacy database framework because i found out that with the same SELECT in the legancy it works and in the DB table selector doesn’t work. I don’t exactly know why, to be honest. I get this error message in DB Table selector node:

Many thanks,
Riccardo

Hello Ricardo,
the problem is that the Evaluate button tries to minimize the computational effort for the dbs and only requests a small amount of rows to be returned. To do so it issues a LIMIT query which most databases do support. Unfortunately Teradata does not support this syntax but uses the TOP syntax. So if you close the dialog and execute the node it should work just fine if the query is correct.

You can also change the Database type of the registered driver to mssqlserver in which case KNIME then does no longer use the SQL92 standard to create SQL queries but the Microsoft SQL Server dialect which uses TOP instead of LIMIT.

Bye
Tobias

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