Databases

Database operations

Joins

Have index common to two tables

Cross join

Keep all columns. can name [table name].[column name] to preserve any differences. including for index (could be missing for some)

Not really matched if original n length, and other m, then new is n*m length. so all combinations of matches are kept

Inner join

Drops those where no match. means data dropped in index missing

Any predicate, equi join, equality predicate

Outer join

Keep data if none matches. left outer join for one table, right outer join for other, or full outer join

Insert

Select

Update

Delete

Call

Create, read, update and delete (CRUD)