What is SQL FROM Clause?

 The SQL FROM clause is used to list the tables and any joins required for the SQL statement.

SQL: FROM Clause

The SQL FROM clause is used to list the tables and any joins required for the SQL statement.

Syntax

The syntax for the FROM Clause in SQL is:

FROM table1
[ { INNER JOIN
  | LEFT [OUTER] JOIN
  | RIGHT [OUTER] JOIN
  | FULL [OUTER] JOIN } table2
ON table1.column1 = table2.column1 ]

Parameters or Arguments

table1 and table2

These are the tables used in the SQL statement. The two tables are joined based on table1.column1 = table2.column1.

Note;

• When using the FROM clause in a SQL statement, there must be at least one table listed in the FROM clause.
• If there are two or more tables listed in the SQL FROM clause, these tables are generally joined using INNER or OUTER joins.

Example - One Table Listed in the FROM Clause

We'll start by looking at how to use the FROM clause that lists only a single table in the SQL statement.

In this example, we have a table called suppliers with the following data:

supplier_id	supplier_name	city	state
100	Microsoft	Redmond	Washington
200	Google	Mountain View	California
300	Oracle	Redwood City	California
400	Kimberly-Clark	Irving	Texas
500	Tyson Foods	Springdale	Arkansas
600	SC Johnson	Racine	Wisconsin
700	Dole Food Company	Westlake Village	California
800	Flowers Foods	Thomasville	Georgia
900	Electronic Arts	Redwood City	California

Enter the following SQL statement:

SELECT *
FROM suppliers
WHERE supplier_id < 400
ORDER BY city DESC;

There will be 3 records selected. These are the results that you should see:

supplier_id	supplier_name	city	state
300	Oracle	Redwood City	California
100	Microsoft	Redmond	Washington
200	Google	Mountain View	California