SQL Server COS()

SQL Server COS() Function

The SQL Server COS() function returns the cosine of a specified angle in radians. This function is useful for performing trigonometric calculations.

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Syntax

SELECT COS(angle);

The COS() function takes a single argument:

• angle: The angle in radians for which to calculate the cosine.

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Example SQL Server COS() Function Queries

Let's look at some examples of SQL Server COS() function queries:

1. Basic COS() Example

SELECT COS(0) AS result;

This query returns the cosine of 0 radians. The result will be:

result
------
1.0

2. COS() with π/2 Radians

SELECT COS(PI()/2) AS result;

This query returns the cosine of π/2 radians (90 degrees). The result will be:

result
------
0.0

3. COS() with a Column

SELECT angle_value, COS(angle_value) AS cos_value
FROM angles;

This query returns the cosine of the angle_value column for each record in the angles table. The result will show the original angle_value and its corresponding cosine as cos_value.

4. COS() with a Variable

DECLARE @angle FLOAT;
SET @angle = PI()/3;
SELECT COS(@angle) AS result;

This query uses a variable to store an angle and then returns its cosine. The result will be:

result
------
0.5

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Full Example

Let's go through a complete example that includes creating a table, inserting data, and using the COS() function.

Step 1: Creating a Table

This step involves creating a new table named example_table to store some sample data.

CREATE TABLE example_table (
    id INT PRIMARY KEY,
    angle_value FLOAT
);

In this example, we create a table named example_table with columns for id and angle_value.

Step 2: Inserting Data into the Table

This step involves inserting some sample data into the example_table.

INSERT INTO example_table (id, angle_value) VALUES (1, 0);
INSERT INTO example_table (id, angle_value) VALUES (2, PI()/2);
INSERT INTO example_table (id, angle_value) VALUES (3, PI()/3);
INSERT INTO example_table (id, angle_value) VALUES (4, PI());

Here, we insert data into the example_table.

Step 3: Using the COS() Function

This step involves using the COS() function to return the cosine of the angle_value column.

SELECT id, angle_value, COS(angle_value) AS cos_value
FROM example_table;

This query retrieves the id, angle_value, and the cosine of the angle_value column for each row in the example_table. The result will be:

id  angle_value  cos_value
--- ------------ ---------
1   0            1.0
2   1.5707963268 0.0
3   1.0471975512 0.5
4   3.1415926536 -1.0

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Conclusion

The SQL Server COS() function is a powerful tool for returning the cosine of a specified angle in radians. Understanding how to use the COS() function and its syntax is essential for effective trigonometric calculations and data processing in SQL Server.