Need a Trigger to duplicate rows in the same table - MySQL

Need a Trigger to duplicate rows in the same table - MySQL

My DB have a table named Order_items in this table I have:
Product_ID, Poduct_sku, Product_Quantity...

What I need is to create 1 more column named: Other_1 that update every time (trigger) with the value equal of Product_Quantity when a new row is inserted.

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Requirements

• If you know what need to be done, please bid
• Changes done in db should be documented for future reference

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Skills Required

mysql