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Caller Workflow with parallel Access to SQL Database

<p>Several examples of how to call a workflow.</p><p>One exampel how to call workflows in parallel chunks and access a SQL database</p>

URL: use parallel chunks to call a sub-workflow to access a database/SQL connection https://forum.knime.com/t/parallel-processing-of-multiple-excel-files-based-on-dynamic-sheet-names-from-list-files-folders-node-in-knime/84034/7?u=mlauber71
URL: Hub: Call Workflow - Main https://forum.knime.com/t/call-workflow-table-based-not-accepting-variable-with-path/48189/6?u=mlauber71

Prepare a database where each "file" from the meta list has its own table in the DB

The Callee Workflow "../Callee_DB_Access" will access the Database (H2) and try to utilize parallel connections

https://forum.knime.com/t/parallel-processing-of-multiple-excel-files-based-on-dynamic-sheet-names-from-list-files-folders-node-in-knime/84034/7?u=mlauber71

In order to get a Workflow Service Input / Output other than the table connection you have to:

  • drag the connection of the type you want from the previous node

  • until a transparent plus sign appears

  • then you search for the "Workflow Service Output"

  • when you click this it will change the type from table to the type you were just dragging along ....

THX to Linh for this insight ...

https://forum.knime.com/t/call-workflow-table-based-additional-table-input-ports-possible/83894/2?u=mlauber71

Merge Variables
Table Row to Variable Loop Start
Pretend this is your Excel Reader
Variable to Table Row
DB Writer
Data Generator
if($$["file"]=="a",0,1)
Variable Expression
Constant Value Column Appender
Cluster_Membership
Column Renamer
Table Row to Variable Loop Start
reset the report filecollect_reports.csv
Delete Files/Folders
Try (Variable Ports)
Variable Loop End
collect_reports.csv
CSV Writer
Path to String
Catch Errors (Var Ports)
CASE Switch Start
../CalleeWFB
Call Workflow Service
CASE Switch End
Parallel Chunk Start
Variable Loop End
Merge Variables
../CalleeWFA
Call Workflow Service
../Callee_DB_Accesscontains a DB Query andand export to Excel
Call Workflow Service
collect information
Variable to Table Row
represents a database? does your DB support parallel accesses ?
H2 Connector
Parallel Chunk End
../CalleeWFB
Call Workflow Service
filea, b, c,d ...
Table Creator

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