Should I use an int or a long for the primary key in an entity framework model

user3736648 picture user3736648 · Jul 21, 2014 · Viewed 12.9k times · Source

I am writing an MVC5 Internet application and I have a question about the id field for a model.

Should I use an int or a long for the id in a model? I am talking about the field that is used for the primary key? Is an int enough if the database has 100,000s of records? Is an int in c# different than an int in a SQL database?

Thanks in advance

Answer

marc_s picture marc_s · Jul 21, 2014

With a type INT, starting at 1, you get over 2 billion possible rows - that should be more than sufficient for the vast majority of cases. With BIGINT, you get roughly 922 quadrillion (922 with 15 zeros - 922'000 billions) - enough for you??

If you use an INT IDENTITY starting at 1, and you insert one row every second, around the clock, you need 66.5 years before you hit the 2 billion limit ....

If you use a BIGINT IDENTITY (BIGINT in T-SQL is defined as long or Int64 in .NET languages) starting at 1, and you insert one thousand rows every second, you need a mind-boggling 292 million years before you hit the 922 quadrillion limit ....

Read more about it (with all the options there are) in the MSDN Books Online.