Introduction to SQL NOT IN
SQL NOT IN statement is used in SQL to specify multiple parameters as the parameters to the function so that the resulting records will not contain any record having value of the column as specified in the NOT IN statement. The NOT IN statement of SQL works similar to the specification of multiple OR conditions on the particular column in the WHERE clause. NOT IN is a short form of multiple OR in WHERE clause. In this article, we will learn about the syntax and usage of the NOT IN statement in SQL and then further, with the help of examples, understand how we can use the NOT IN statement in SQL to specify the condition that mentions how to exclude records of particular values.
Syntax and usage
The syntax of the NOT IN statement in SQL is as shown below –
column_name NOT IN (expression1, expression2, ...);
We can use the above syntax in the WHERE clause while using any of the DML statements of SQL such as SELECT, UPDATE, INSERT, and DELETE. The column_name in the syntax is the name of the column of the table on which the query is being applied for which we have to specify the condition that the value of the column should not contain the expression values mentioned in the list containing comma-separated expression that evaluates to values that need to be excluded for column value.
The expressions mentioned inside the parameters of the NOT IN clause can be the literal values, variables, names of the columns of other tables, or an all different subquery resulting in the records containing the values to be excluded for the column named column_name in the query. We will learn how we can implement the NOT IN statement inside the queries operating on tables and involving fetching, updation, insertion, and removal of the records one by one using examples.
Examples
We will study the working of NOT IN constraint by using it in different DML statements of SQL such as SELECT, INSERT, UPDATE and DELETE.
Let us create two tables named educba_learning and educba_writers using the following create table statements.
CREATE TABLE `educba_writers` (
`id` INT(11) NOT NULL,
`firstName` VARCHAR(10) NOT NULL,
`rate` DECIMAL(5,2) DEFAULT NULL,
`joining_date_time` DATETIME DEFAULT NULL
);
The execution of the above query statement will give the following output –
CREATE TABLE `educba_learning` (
`topic_id` INT(11) NOT NULL IDENTITY,
`subject` VARCHAR(100) DEFAULT NULL,
`sessions` INT(5) DEFAULT '0',
`expert_name` VARCHAR(100) DEFAULT NULL,
`charges` DECIMAL(7,2) DEFAULT '0.00'
);
The execution of the above query statement will give the following output –
Now, we will insert some records in both of the tables –
INSERT INTO `educba_learning` (`topic_id`, `subject`, `sessions`, `expert_name`, `charges`) VALUES
(1, 'SQL', 750, 'Payal', '3750.00'),
(2, 'MySQL', 700, 'Vyankatesh', '3500.00'),
(3, 'PostgreSQL', 600, 'Omprakash', '3000.00'),
(4, 'Hadoop', 980, 'Parineeta', '4900.00');
The execution of the above query statement will give the following output –
INSERT INTO `educba_writers` (`id`, `firstName`, `rate`, `joining_date_time`) VALUES
(1, 'Payal', '750.00', '2020-05-28 16:02:34'),
(2, 'Vyankatesh', '700.00', NULL),
(3, 'Omprakash', '600.00', '2020-05-28 20:32:50'),
(4, 'Parineeta', '980.00', NULL);
The execution of the above query statement will give the following output –
As you can see, we have inserted some records in both the tables.
Let us retrieve the contents of both tables.
Executing the select query mentioned below for the educba_learning table gives the following output –
SELECT * FROM `educba_learning`
Executing the select query for educba_writers table gives the following output –
Now, we are ready to use the NOT IN constraint on the above tables. We will see examples of each of the DML statements one by one.
Using NOT IN constraint with the select query
Let us consider one example using the above tables and retrieve the records of the table educba_writers not having rate 650 or 700 as the column value of rate column using the NOT IN clause in the SELECT query statement. Our query statement will be as shown below.
SELECT * FROM `educba_writers` WHERE rate NOT IN (650,700);
The output of the execution of the above query statement is as follows, containing the records of the table educba_writers for which the column of rate does not have the value of 650 or 750 in it –
Using NOT IN constraint with the update query
While updating the records, there might be a scenario where you want to update only those records not having values of certain columns set to some specified values. Now, we have to change the name of the expert to “Smita” in the table educba_learning, where the subject value does not contain the value as SQL, MySQL, and PostgreSQL. We will use the NOT IN operator in the where clause of the update query to satisfy our condition using the following query statement –
UPDATE educba_learning
SET expert_name = "Smita"
WHERE SUBJECT NOT IN ("SQL" , "MySQL" , "PostgreSQL");
The execution of the above query statement will give the following output –
Let us check the contents of the table educba_writers after updating and see which records have been updated.
SELECT * FROM `educba_learning` ;
The execution of the above query statement will give the following output having recorded with subject Hadoop having the expert name as Smita –
Using NOT IN constraint with the delete query
Let us now use the subquery instead of specifying the literal values in the NOT IN statement. We have to use a delete query statement to delete those values of the table educba_learning whose expert name field has the value that is not present as the first name in the educba_writers table. For this, we will use the subquery to retrieve all the writers from the educba_writers table, and our query statement will be as follows –
DELETE FROM educba_learning
WHERE expert_name
NOT IN (SELECT firstName FROM educba_writers);
The execution of the above query statement will give the following output –
Let us retrieve the values of the educba_learning table and see whether the record with Smita as expert name got deleted –
SELECT * FROM `educba_learning`;
The execution of the above query statement will give the following output with the expected records in it –
Conclusion – SQL NOT IN
We can apply the constraint on one or more columns to mention that the value of that column should not be present in the list of values mentioned inside the NOT IN statement. This constraint can be used in either of the DML statements in SQL: SELECT, INSERT, UPDATE, and DELETE.
Recommended Articles
We hope that this EDUCBA information on “SQL NOT IN” was beneficial to you. You can view EDUCBA’s recommended articles for more information.