WHERE and ORDER BY clause

* WHERE clause is used as a filter on the table  to get a desired output. It is used to full fill a given condition. 

Syntax:- 

SELECT column_name 

FROM table_name 

WHERE search_condition

ORDER BY expression;

• WHERE clause appears after the FROM clause but before the ORDER BY clause. 
• WHERE clause not only is used in SELECT statement but also in the UPDATE and DELETE clause.
• We use ORDER BY clause at the very end of the query.

• Lets say we have the emp table:

and we want the names of the employees who's salary is greater than 2000.

• So we will write a query:

• As we can see, the data is now filtered out. Earlier there were 14 rows but now after using WHERE clause we have 6 rows. 
• We always use WHERE clause with comparison operators like: 

Now lets see ORDER BY clause:

• Say we have the same query viz "SELECT * FROM EMP WHERE SAL>2000;" but now we want the data to be sorted in ascending order of sal column then we write--

SELECT * FROM EMP WHERE SAL>2000 ORDER BY SAL;

• We can see the SAL column is now sorted in the ascending order. If we want to sort the data by descending order then just write desc viz a shorthand for descending.

SELECT * FROM EMP WHERE SAL>2000 ORDER BY SAL DESC;

• We can also filter the data with the help of one or more columns
• We can even display one or more columns.