SQL Functions.

Sql Has Several Built-in Functions That Can Be Used To Perform Calculations, Manipulate Strings, Work With Dates, And Perform Various Other Tasks. Here Are Some Examples Of Commonly Used Sql Functions:

1. Sql Aggregate Functions: Aggregate Functions Are Used To Perform Calculations On A Set Of Values And Return A Single Result. Examples Of Aggregate Functions Include Sum, Avg, Count, Min, And Max. For Example, To Find The Total Sales Amount In A Table Named "Orders," You Can Use The Following Sql Statement:

   SELECT SUM(sales_amount) FROM orders;

2. Sql String Functions: String Functions Are Used To Manipulate Strings Or Text Data. Examples Of String Functions Include Concat, Length, Substring, And Upper/Lower. For Example, To Concatenate Two Columns "First_Name" And "Last_Name" Into A Single Column "Full_Name" In A Table Named "Customers," You Can Use The Following Sql Statement:

   SELECT CONCAT(first_name, ' ', last_name) AS full_name FROM customers;

3. Sql Date Functions: Date Functions Are Used To Work With Dates And Times. Examples Of Date Functions Include Date, Dateadd, Datediff, And Day. For Example, To Find The Number Of Days Between Two Dates In A Table Named "Orders," You Can Use The Following Sql Statement:

   SELECT DATEDIFF(day, order_date, ship_date) AS days_to_ship FROM orders;

4. Sql Scalar Functions: Scalar Functions Are Used To Perform Calculations On A Single Value. Examples Of Scalar Functions Include Round, Ceiling, And Floor. For Example, To Round A Numeric Value "Price" To Two Decimal Places In A Table Named "Products," You Can Use The Following Sql Statement:

   SELECT ROUND(price, 2) AS rounded_price FROM products;

It's Important To Note That The Syntax And Usage Of Sql Functions Can Vary Depending On The Specific Database Management System Being Used. It's Always Recommended To Refer To The Documentation And Resources Provided By The Database Management System For Specific Information On Syntax And Usage.