Our customers are using different CRM (Customer relationship management) and ERP (Enterprise Resource Planning) systems. The most uses systems From a data integration perspective, this is important because our extraction processes will need to work with data from these different systems either directly or indirectly.
The most widely used systems by our customers are:
SAP 4 Hana: https://searchsap.techtarget.com/definition/SAP-S-4HANA
Salesforce: https://www.salesforce.com/products/what-is-salesforce/
Microsoft Dynamic: https://dynamics.microsoft.com/en-us/
IBM AS 400.
Some customers have their own built system.
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For communication within the data integration process with these systems, CSV/XML files are transferred via one of these methods; SFTP or , S3 storage or API which these systems provide which are usually , or a REST or SOAP API call .It is good if the integration engineer has user or technical experience with some of these systems.(which is provided by these CRM systems noted above)