The following code combines Google Apps Script and SQL to bulk insert a Google Sheet of data into an existing SQL Table, but only after checking the record does not already exist so that it can be safely re-run.
Source: The Gift of Script: Bulk add unique data to an SQL Table in Apps Script
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I use Google Apps Script to support staff and students in my job. I enjoy dabbling with creating tools to help with automation and I freely share my learning experiences on my blog, where I also have a number of useful Google Add-ons: www.pbainbridge.co.uk