PHP/MySQL: Update if Exist or Insert if Not
You seek to update a MySQL table if specific fields exist, or insert if they do not. This scenario involves joining three tables: set_colors, school_art, and baseimage.
To achieve your desired outcome, consider the following code:
This updated code employs the INSERT ... ON DUPLICATE KEY UPDATE statement in MySQL. It performs the following actions:
- Inserts new rows if the (school_art_id, baseimage_id) pair is not found.
- Updates existing rows if the (school_art_id, baseimage_id) pair already exists.
- In case of an update, only the sub_folder and layer columns are updated to the values provided in the VALUES clause.
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