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.

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