About SQL Alias (alias) in PHP

SQL Alias

SQL Alias syntax for tables

SELECT column_name (s) from Table_nameas Alias_name

SQL Alias syntax for columns

SELECT column_name as Alias_namefrom table_name

Alias instance: Using Table name aliases

Let's say we have two tables: "Persons" and "Product_orders", respectively. We assign them the alias "P" and "Po", respectively.

Now we want to list all orders for "John Adams".

We can use the following SELECT statement:

SELECT Po. OrderID, P.lastname, P.firstnamefrom Persons as P, product_orders as Powhere p.lastname= ' Adams ' and p.firstname= ' John '

SELECT statements that do not use aliases:

SELECT Product_orders.orderid, Persons.lastname, Persons.firstnamefrom Persons, Product_orderswhere Persons.LastName = ' Adams ' and persons.firstname= ' John '

As you can see from the two SELECT statements above, aliases make the query program easier to read and write.

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