How to split output by separator from sql string?

Question

PHP

There is a table
Structure
1. product_id
2. upc

Data
1. 63054
2. 996=8;939=8;940=8;941=2

separator character ";"
key=value through equals

How can I display in php that the keys and values ​​would be displayed separately by type.
product_id = 63054
key = 996
value = 8

product_id = 63054
key = 940
value = 8

product_id = 63054
key = 941
value = 2

per row depending on the number of keys and values.
If there is no value but there is a key, then the line is not displayed.
And if there is no separator at the end, then read whether there is a key value before the separator.
I understand that you need to display the array and parse it, but nothing happens.

Upc values ​​can be more than 3, this is just an example

Answer 1

explode