In Structured Query Language (SQL), a JOIN is a method of linking two data tables in a single query, allowing the database to return a set that contains data from both tables at once, or using data from one table to be used as a Filter on the second table. There are several types of JOINs defined within the ANSI SQL standard.
In SQL Server, a procedure is a stored program that you can pass parameters into. It does not return a value like a function does. However, it can return a success/failure status to the procedure that called it.
In SQL Server,
NULL represents data that is missing, or unknown. This means that
NULL is not really a value; it's better described as a placeholder for a value. This is also the reason why you can't compare
NULL with any value, and not even with another
The INSERT INTO statement is used to insert new records in a table.