? COUNT with WHERE Clause in SQL

You can use the COUNT() function together with a WHERE clause to count rows that meet a specific condition.

? Syntax

SELECT COUNT(*)FROM table_nameWHERE condition;

? Example

Suppose you have a table employees and want to count how many employees are in the Sales department:

SELECT COUNT(*) AS sales_countFROM employeesWHERE department = 'Sales';

? Counting Non-Null Values with Condition

SELECT COUNT(email) AS emails_in_salesFROM employeesWHERE department = 'Sales';

• Counts non-null email values only for employees in Sales.

? Using COUNT with Conditional Aggregation

Sometimes you want to count based on a condition but within a single query without filtering rows:

SELECT    COUNT(CASE WHEN department = 'Sales' THEN 1 END) AS sales_count,    COUNT(CASE WHEN department = 'HR' THEN 1 END) AS hr_countFROM employees;

If you want, I can provide examples with more complex conditions or grouping!