Most scenarios, it needs to be fetch the data from DE. You can achieve this using SSJS or AMPScript in Salesforce Marketing Cloud.
If there need to fetch the logs for Row Set Transformation Toolkit,Remote Complex Object Instance Service,Pricing Manager,EAI Siebel Adapter business service, copy below code. Compile Business Service. Logs will get created in Logs folder.
In Siebel,How to read File Names from specific Folder in VBScript
If user wants to loop multiple records in workflow without using any BusComp Operation Step to update/insert/query multiple records then Siebel has given a vanilla BS for same.
How to query record without using Siebel Operation step and BusComp not exists in BO in Workflow
Update Record without using Siebel Operation step in Workflow is Siebel
Scenarios to Display “Total Revenue” on Account-Opportunity List Applet