Update with Join SQL Server

Hello Dev, welcome to this journal article on Update with Join SQL Server. In this article, we will provide a comprehensive guide on how to update data in a table by joining it with another table in SQL Server. This article is designed to provide a step-by-step guide to SQL developers with some basic knowledge of SQL Server.

What is Update with Join SQL Server?

The Update with Join SQL Server is a type of SQL join statement used to update data in a table by joining it with data from another table. This statement can be used when you need to update one or more columns in a table with the data from another table.

For instance, suppose you have a table of customers and another table of orders. You want to update the customers’ table with their most recent order date from the orders table. You can use the Update with Join SQL Server statement to update the customers’ table with the latest order date.

How to Use Update with Join SQL Server?

The Update with Join SQL Server statement can be used in two ways – with or without an alias. The syntax for this statement is as follows:

Syntax
UPDATE table1
SET table1.column1 = table2.column1, table1.column2 = table2.column2, …, table1.columnN = table2.columnN
FROM table1
JOIN table2 ON table1.join_column = table2.join_column
WHERE condition

The Update with Join SQL Server statement uses the UPDATE, SET, FROM, JOIN, and WHERE clauses. The UPDATE clause specifies the name of the table to be updated. The SET clause sets the column values to be updated using the data from the other table. The FROM clause specifies the table to join with, and the JOIN clause specifies the join condition. The WHERE clause is used to filter the rows to be updated.

Examples of Update with Join SQL Server

Let’s look at some examples of how to use Update with Join SQL Server statement.

Example 1:

Update the employees’ salary in the employee table with the highest salary value in the salaries table.

employee table	salaries table
id	employee_id
name	salary
salary	start_date
	end_date

The SQL statement to update the employees’ salary in the employee table will be:

SQL Statement
UPDATE employee
SET employee.salary = salaries.salary
FROM employee
JOIN (SELECT employee_id, MAX(salary) AS salary FROM salaries GROUP BY employee_id) salaries ON employee.id = salaries.employee_id

The above SQL statement updates the salary column in the employee table with the maximum salary value from the salaries table.

Example 2:

Update the students’ grades in the students table with their final exam score in the exams table.

students table	exams table
id	student_id
name	course
grade	score

The SQL statement to update the students’ grades in the students table will be:

SQL Statement
UPDATE students
SET students.grade = exams.score
FROM students
JOIN exams ON students.id = exams.student_id AND exams.course = ‘Final Exam’

The above SQL statement updates the grade column in the students table with the final exam score from the exams table.

FAQ

Q1. When should I use Update with Join SQL Server?

A1. Update with Join SQL Server should be used when you need to update one or more columns in a table with the data from another table.

Q2. How does Update with Join SQL Server work?

A2. Update with Join SQL Server works by joining the table to be updated with another table using a common column and updating the data in the target table with the data from the joined table.

Q3. Can I use multiple tables while using Update with Join SQL Server?

A3. Yes, you can use multiple tables while using Update with Join SQL Server.

Q4. What is the difference between Update with Join SQL Server and Update statement?

A4. The Update statement can update data in a single table, whereas Update with Join SQL Server can update data in a table by joining it with data from another table.

Q5. Is Update with Join SQL Server supported in all SQL Server versions?

A5. Yes, Update with Join SQL Server is supported in all SQL Server versions.

In conclusion, the Update with Join SQL Server statement is a powerful tool to update data in a table by joining it with data from another table. It can be used in many scenarios where you need to update data in a table with information from another table. We hope this comprehensive guide has provided you with a better understanding of how to use Update with Join SQL Server.