Using external API with php/mySql:

General information for the website: getting info from API into sql-table(s)
Num. of web pages/modules: 1
Description of requirements/features: Hi,
I have a very small project that is almost complete. The project is meant to extract weather information from an external API, and store it. I need 2 things to wrap it up:

1. I have 3 sql-tables: user, cities, citydata. Every user in the user-table has a city-ID. This city id represents an ID in the city-table (for example, London has ID 1, so if the city-id of the user is 1, this means he lives in London). I need the code to fetch the data associacated with the user's city id from the other 2 tables (cities+citydata) and store them in strings/variables.

2. Call the method that calls the API, passing strings/variables for city name and countrycode. I have the method done, and the drop down list for choosing city as well. What I need you to do is store the data returned from the API into the correct columns in the table city-data. Also, the new city selected should replace the old one of the user-table too (if user has London when logging in, but select to check weather of Tokyo, Tokyo will be his new city)

These tasks should be very easy for you to do, if you're experienced in php/mySQL.
IMPORTANT: I want you to just make the above happen. I don't want you to "improve" any of my existing code unless it is absolutely needed to make it work. Don't overdo it, keep it simple.
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