Mongo's ObjectID is defined like this: ObjectId is a 12-byte BSON type, constructed using: a 4-byte value representing the seconds since the Unix epoch, a 3-byte machine identifier, ...
I'm trying to build a aggregated reader website of multiple forums. Because most queries are likely to be within same time periods for written_time column, I'm thinking about taking advantage of ...
Why are runtimes different for a table including a primary key versus a table with a clustered unique index added after population
When I create a temporary table with a PK defined from the outset like this I get great performance in subsequent joins on that key: create table #temp ( field1 int not null field2 int ...
Can I have create an InnoDB table without a PK? If so, would a secondary index be used as the clustered index?
Is it possible to create an InnoDB table without a Primary Key? Since InnoDB tables are structured as clustered index around the PK, what would be the structure of a table without PK? Would that ...
I understand that there may be a difference in meaning or intent between the two, but are there any behavioral or performance differences between a clustered primary key and a clustered unique index?