How to store a 2D array in a MYSQL row?
arrays, json, mysql
Solution
Well you can always store 2D array in a column of a database but there is a problem with it, i.e retrieving data from mysql you'll have to parse that column and that column of yours will contain multiple values. When you have a multivalued attribute in your table it must be migrated to another table to normalize your database design.
In your case you are looking at many-to-many relation ship i.e a package may have many items and an item may be taken by many packages. To solve many-to-many relation you have to introduce a new table usually called a Bridge table. that bridge table will take Primary Keys from both item and package tables as Foreign Keys. The reason you add this table is to remove redundancy and that is one of many things normalization is offering.
Problem
This might not even be possible to do. I have one table that contains items. (item_id, item_name, description, json for deserializing into an actual object) My second table contains packages. (package_id,package_name,price,description,item_list(2D array)) The 2D array needs to match item_id values to quantities. Normally, I would simply serialize a JSON array to the item list spot. I worry about item_id values being removed or changed though. I cannot use a foreign key to have a change "cascade" or "delete" child values. Is there a way to store a kind of sub-table in a mysql row? Let me know if my problem description is not clear. I want to make sure it is followable for anyone else who is trying to find an answer. I might include some images later if it will help. Solution: No, there isn't a way to store a 2D array in a MySQL row. You have to use a bridge table. Oh well, at least there is a solution. A solution always exists.