Extract data from db using value from other db

[takbb]

Hi @chiashin , and welcome to the KNIME community.

Yes this is possible.

Here is a demonstration workflow that reads one database and then uses data from that to form an IN query to be used against a different database.

Querying database based on values from another database.knwf (52.0 KB)

In the above workflow, the creation of the delimited items for the IN query uses a component that I wrote specifically for this type of scenario, but this can also be achieved using a combination of GroupBy and String manipulation nodes, or possibly other methods (see the posts below for more info). I find it convenient to just use a component for it though

Table Column to Delimited String – takbb

You may find the following forum topics useful as they discuss the creation of an IN clause, and other comma-delimited clauses for use against a database, providing different ideas and approaches:

Use comma separated variable to produce a SQL query string

Hello, i have a situation in which an user should instantiate a variable done like that: Locations => 1 , 2 , 5 , 9 Doing some manipulation i have to use this information to make a column with a sql query like that: select staticfield, anotherstaticfield, hellofield, “dynamicfields” from table where “dynamiccondition” where dynamicfields is: Location1, Location2, Location5, Location 9 dynamiccondition is: (Location1 <>0 or Location2<>0 OR location5<>0 or Location9 <>0) I did this: 1- cr…

DB row Filter with String Widget

Hi All, I have a table which has over 10 million rows. I want to filter on a column which is categorical and i want the user to select multiple categories right at the start of the query. I don’t want the DB Reader node first since that takes in a lot of time. How do i add a list of my choices as a flow variable to my condition in the DB row filter? For example:- My DB Table selector has a custom query select a,b,c,d from xyz; then DB row filter has a condition of b = ‘1234’ set i am conn…