PHP 逐行读取 CSV 文件 - 比较上一行中的数据

Question

I have a script set up that reads uploaded CSV files line by line. There are about 15 columns in each CSV file. The file has up to 8 contact people for each row, and each row has a "case number" that acts as a unique ID for each row. My script then adds those contact people to a database, line by line for however many lines there are.

Now, things have changed outside of my control. Each contact person is entered onto each line, and that case number number may show up on multiple lines now.

I'm having trouble on how to pursue this now. I need to be able uploaded the contacts with the same case number to the same row. So I would need to INSERT the initial showing of the contact person, and then UPDATE SET that row each time another contact person is encountered with the same case number within my loop.

I don't have any code to show. I'm just having trouble with how to approach this logistically. I will probably be downvoted, but I'll keep trying things on my end.

Answer 1

I ended up inserting all of the data into a table, and then querying that table for the unique identifier, and then populating a different table with that unique identifier and all of the contacts that had that identifier. I was over complicating this from the beginning but it's good to know about INSERT ON DUPLICATE KEY UPDATE