Drupal best practice question

Hi,

I have a table in my database that I access that gives me information about a group such as group name, group purpose etc…, that group has members and I d like to capture the uid of all the groups members and save that, should I save it all as an array in a single field in my database (Never going to be more than about 30 members per group) or should I create a second table and store the information there? What is the recommended way to solve this common problem please.

Sorry if this is a daft question, I am new to coding in D7, loving learning how to write custom modules and just want to make sure I do this right from the start

Many Thanks

Gibbo

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