KNIME 3.6 Database Reader not Retrieving New Content after Reset for MS-Access

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1

I’m using Windows 7 Enterprise. To get updated content I need to restart KNIME.
UcanAccess v.4.04. This happened after Database Reader was twice reset.
Even then I changed sql script result did not been read from the database but from kind of cach.

Please, advise.

2

Dear @izaychik63,

Just to get this right: do you mean that when you reset and re-execute a Database Reader node, it does not fetch new content from the database?

How exactly was the new content added to the database?

Best,
Stefan

3

Yes, Database Reader not fetch new content. Content is inputted through an Access application. The changes I made ware name corrections (space deletion, letters capitalization).
To get new content I need to restart KNIME.

4

Hi,
this is a limitation of the UCanAccess library which only has limited concurrent usage support. For more details see this blog post.
Bye
Tobias

5

From what I read on forum my situation is different. I do not write using UcanAccess. I just read from from KNIME same Access DB. Anyway, it sounds odd that before you close KNIME you can not see changes done. Is it possible on Database Reader reset to disconnect it from the DB? This will resolve the problem.

6

The existing database framework caches the connection globally and closes it only when KNIME is shutdown. You can try out the new database framework which closes the connection when the corresponding DB Connector node is reset. To try it you need to install the KNIME Database (preview) extension

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Once installed you need to register the UCanAccess driver again via the new Database (Labs) preference page. All new DB nodes are located in the KNIME Labs category
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Bye
Tobias

1 Like
7

Thank you, Tobias. Should I replace all DB related nodes after installation or they still will work?

8

You will have to replace all the DB related nodes since the ones in Labs are not compatible with the “regular” ones.

1 Like
9

Will all DB nodes stop to work in KNIME 3.7 as well or they will as legacy? To loose dozens of nodes functionality at once is a high risk.

10

You will be able to run workflows with deprecated nodes in any case.

I am not entirely sure what you mean by that: Are you missing functionality with the new DB nodes? Getting feedback from our community is exactly why we are releasing new functionality as Preview.

11

Thank you for explanation. It was important to know that deprecated nodes will continue to work.

1 Like
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