Questions on Unique and Auto-increment

[Earl Melton <earlemelton yahoo com>]

Hello,

I am new to Linux/Ubuntu and even newer to Glom, so I'm likely to be asking a lot of questions that will make most of you yawn and say, "Oh no, another one of those!" Here are the first two:

I'm trying to set up a rental management database, currently with 14 tables, but that may grow in time to come. When I click on Developer > Fields, I see on the PK that Unique is checked on some tables and not on others. Shouldn't that be a unique number on [all] PKs? Maybe I don't understand what unique means here.

Also, from the same dialog box, when I right-click on a PK and choose Edit, Auto-increment is not checked. I [think] this is true on all tables, but not 100% certain yet. Wouldn't it be a good idea to tick this checkbox to be sure the number changes on each record? Another way to word this question: when would I [not] want the PK to auto-increment?

TIA for your help! I'll pose another question in a separate e-mail.
 

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Have a blessed day!
 <>< Earl

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