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MS SQL Server - count if

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Created by:

Roseanne-Read

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In this article, we would like to show you how to count rows when the expression is true in MS SQL Server.

Quick solution:

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SELECT COUNT(CASE WHEN expresion THEN 1 END)

Note:

Go to this article to read more about CASE statement.

Practical example

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To show you how IF() function works, we will use the following users table:

Note:

At the end of this article you can find database preparation SQL queries.

Example

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In this example, we will count the number of users whose salary is high, average or low.

Query

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SELECT 
    COUNT(CASE WHEN [salary] = 6000 THEN 1 END) AS 'high_salary',
    COUNT(CASE WHEN [salary] = 4000 THEN 1 END) AS 'average_salary',
    COUNT(CASE WHEN [salary] = 2000 THEN 1 END) AS 'low_salary'
FROM [users];

Result:

Database preparation

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create_tables.sql file:

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CREATE TABLE [users] (
    [id] INT IDENTITY(1,1),
    [name] VARCHAR(50) NOT NULL,
    [surname] VARCHAR(50) NOT NULL,
    [department_id] INT,
    [salary] DECIMAL(15,2) NOT NULL,
    PRIMARY KEY ([id])
);

insert_data.sql file:

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INSERT INTO [users]
    ( [name], [surname], [department_id], [salary])
VALUES
    ('John', 'Stewart', 1, '6000'),
    ('Chris', 'Brown', 2, '6000'),
    ('Kate', 'Lewis', 3, '4000'),
    ('Ailisa', 'Gomez', NULL, '4000'),
    ('Gwendolyn', 'James', 2, '4000'),
    ('Simon', 'Collins', 4, '4000'),
    ('Taylor', 'Martin', 2, '2000'),
    ('Andrew', 'Thompson', NULL, '2000');