LOG Function in SQL

The LOG is a string function in SQL which returns the logarithm of the given number. Or, we can say that, it shows the logarithms of the number to the given base.

Syntax of LOG Function

In the LOG syntax, Number1 must be greater than 0 and it is the number whose log we want to find. Number2 is the base.

In the Structured Query Language, we can also use the LOG function with the columns of the table as shown in the following block:

In this syntax, we have to define the name and columns of that table on which we want to perform the LOG function.

Examples of LOG function

Example 1: This example gets the logarithm of 2:

Output:

Example 2: This example returns the logarithm of 2 by base 2 in the output:

Output:

Example 3: This example returns the logarithm of 8 by base 6 in the output:

Output:

Example 4: This example returns the logarithm of 255 by base 4 in the output:

Output:

Example 5: This example uses the LOG function with the SQL table. In this example, we will create the new table through which we will perform the LOG function on the columns of the table:

The following shows the syntax to create the new table in SQL:

The following CREATE statement creates the Product_Details table for storing the price and quantity of products:

The following multiple INSERT queries insert the records of products with their selling and purchasing price into the Product_Details table:

The following SELECT statement displays the inserted records of the above Product_Details table:

Query 1: The following SELECT query uses the LOG function with the Product_ID column of the above Product_Details table:

This query gives the logarithm of each product_id by base 4.

Output:

Query 2: The following SELECT query uses the LOG function with the Purchasing_Price column of the above Product_Details table:

This query gives the logarithm of each Purchasing_Price by base 10.

Output:

Query 3: The following SELECT query uses the LOG function with the Product_Rating column of the above Product_Details table:

This query gives the logarithm of each rating of products by base 6.

Output:

Query 4: The following SELECT query uses the LOG function with the Selling_Price column of the above Product_Details table:

This query gives the logarithm of each Selling_Price by base 4.

Output: