SQL SET Command: Purpose & Usage Guide

In SQL, SET is a keyword used to update data in a database table. It can update the values of one or more columns in a table based on specified conditions.

The basic syntax of a SET statement is as follows:

UPDATE table_name
SET column1 = value1, column2 = value2, ...
WHERE condition;

In this case, “table_name” refers to the name of the table that needs to be updated, “column1, column2, …” represent the columns to be updated, “value1, value2, …” represent the new values to be updated, and “condition” is the condition for the update.

For example, suppose there is a table called “customers” that contains the following columns: customer_id, customer_name, city, country.

We would like to update the city and country of the customer with ID 1 to “New York” and “USA”, you can use the following SET statement:

UPDATE customers
SET city = 'New York', country = 'USA'
WHERE customer_id = 1;

This will update the values in the city and country columns of the rows in the table that meet the condition to “New York” and “USA”.

It is important to note that in the SET statement, values for one or more columns can be updated, while also being able to specify the update conditions as needed with the WHERE clause.