An alias is a feature of SQL that is supported by most, if not all, RDBMSs. It is a temporary name assigned to the table or table column for the purpose of a particular SQL query. In addition, aliasing can be employed as an obfuscation technique to secure the real names of database fields. A table alias is also called a correlation name .
An alias is represented explicitly by the AS keyword but in some cases the same can be performed without it as well. Nevertheless, using the AS keyword is always a good practice.
SELECT A.emp_name AS "Employee" /* Alias using AS keyword */
B.emp_name AS "Supervisor"
FROM employee A, employee B /* Alias without AS keyword */
WHERE A.emp_sup = B.emp_id;
Posted Date:- 2021-08-17 05:34:54
What is the need for MERGE statement?
Define UNION, MINUS, UNION ALL, INTERSECT?
What is the Cartesian product of the table?
Write a SQL query to find the names of employees that begin with ‘A’?
Are NULL values same as that of zero or a blank space?
What is Collation? What are the different types of Collation Sensitivity?
What is the difference between DELETE and TRUNCATE statements?
What are the different types of joins in SQL?
What are the different operators available in SQL?
Explain different types of index in SQL.
What do you mean by Denormalization?
Write a SQL query to display the current date?
What is the difference between clustered and non-clustered index in SQL?
What is an alternative for TOP clause in SQL?
How do you add a column to a table?
What is Database Black Box Testing?
Explain database white box testing and black box testing.
What is a Relationship? How many types of Relationships are there?
What is the difference between DROP and TRUNCATE?
What are the types of SQL Queries?
How to rename column name in SQL Server?
What is the update command in SQL?
What is a “TRIGGER†in SQL?
What is the need for group functions in SQL?
What are Entities and Relationships?
How many Aggregate functions are available in SQL?
What are the properties of the transaction?
What do you mean by table and field in SQL?
What are the different types of database management systems?