Certified to build ETL (Exchange, Transfer and Load) solutions for Microsoft SQL Server (Holds current MCSA and MCP certifications).
Since this is a one off solution that connects two specific sources, the easiest solution is to extract customer information into a staging area, then use an execute process task to call a script written in one of the standard GetBase client libraries to upsert the extracted records.
Using GetBase's own libraries reduces the likelihood that future upgrades will break the script. I would prefer using the python library, but can use the php or ruby libraries as well. This does require you to have permissions to install software on the client machine.
If you absolutely cannot install software, I can use vba to write a custom driver in SSIS for the GetBase api, though again that has the downside of supporting only the current api version.
Zapier is also a good option, but it requires direct access to the database from an external ip provided by Zapier. This involves changes to both firewall and SQL Server connection settings. If you do not have full, administrative control over your machine, local network, and the SQL Server instance, you'd likely need to have conversations with your IT administrators to enable this. I can walk you through settings changes or apply them if you are in full control of your system(s).
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