What is temporary table and how to implement it in SQL server

A temporary table in SQL Server is a special type of table that is stored in the tempdb database and exists only for the duration of the connection or the user session. They are used to store intermediate results of complex queries and are not permanent like regular tables.

Here is an example of creating and using a temporary table in SQL Server:

— Create a temporary table CREATE TABLE #Employees ( EmployeeID INT, FirstName VARCHAR(50), LastName VARCHAR(50), Salary INT )

— Insert data into the temporary table INSERT INTO #Employees VALUES (1, ‘John’, ‘Doe’, 50000), (2, ‘Jane’, ‘Smith’, 55000), (3, ‘Mark’, ‘Johnson’, 60000)

— Select data from the temporary table SELECT * FROM #Employees

— The result will be: — EmployeeID FirstName LastName Salary — 1 John Doe 50000 — 2 Jane Smith 55000 — 3 Mark Johnson 60000

Note that once the connection is closed or the user session ends, the temporary table will be automatically dropped. To explicitly drop the temporary table, you can use the DROP TABLE statement.