SQL SQRT() function

SQRT() function

SQL SQRT() returns the square root of a given value in the argument.

Syntax:

SQRT( expression )

Parameters:

MySQL, PostgreSQL, SQL Server, and Oracle

All of above platforms support the SQL syntax of SQRT().

SQL SQRT() function: Pictorial presentation

Example :

To get the square root of 36 from the DUAL table, the following SQL statement can be used:

-- This SQL statement calculates the square root of the number 36 and selects the result from the 'dual' table.
SELECT SQRT(36) 
-- SELECT statement retrieves data from the database
-- SQRT() function calculates the square root of a specified number
-- In this case, SQRT(36) calculates the square root of 36
FROM dual;
-- Specifies the 'dual' table, a special one-row, one-column table present in Oracle database
-- The 'dual' table is often used for performing calculations or returning single results in SQL queries

Explanation:

• This SQL query is straightforward, as it's only a single statement.


• The purpose of this query is to calculate the square root of the number 36.


• SQRT() is a mathematical function that calculates the square root of a given number.


• In this case, SQRT(36) will return the square root of 36, which is 6.


• The result of the calculation, which is 6 in this case, will be selected as the output of the query.


• The 'dual' table is used here because it's a convenient way to execute single-row queries in Oracle SQL without needing to specify an actual table with data.

Output:

  SQRT(36)
----------
         6

SQL SQRT() function with distinct

Sample table: customer

To get the unique square root of 'opening_amt' from 'customer' table, the following SQL statement can be used :

-- This SQL statement calculates the square root of the 'opening_amt' column for each row in the 'customer' table.
SELECT SQRT(opening_amt) 
-- SELECT statement retrieves data from the database
-- SQRT() function calculates the square root of a specified number
-- In this case, SQRT(opening_amt) calculates the square root of the 'opening_amt' column value for each row
FROM customer;
-- Specifies the 'customer' table from which the data is being retrieved

Explanation:

• This SQL query is designed to calculate the square root of the 'opening_amt' column for each row in the 'customer' table.


• The SELECT statement specifies the SQRT(opening_amt) expression, which calculates the square root of the 'opening_amt' column value for each row.


• The query is executed against the 'customer' table to retrieve the square root of the opening amounts.


• Each row in the result will have the square root of the corresponding 'opening_amt' value.


• The 'customer' table is used here as the data source for the calculation.

Output:

SQRT(OPENING_AMT)
-----------------
       77.4596669
       54.7722558
       70.7106781
       70.7106781
       63.2455532
       77.4596669
       70.7106781
       83.6660027
       83.6660027
       89.4427191
       83.6660027
       83.6660027
       83.6660027
       70.7106781
       63.2455532
              100
       77.4596669
       89.4427191
       70.7106781
       83.6660027
       89.4427191
       89.4427191
       89.4427191
       89.4427191
       83.6660027

Note: Outputs of the said SQL statement shown here is taken by using Oracle Database 10g Express Edition.

Here is a slide presentation which covers the SQL arithmetic functions.

Check out our 1000+ SQL Exercises with solution and explanation to improve your skills.

Previous: POWER
Next: Character Function