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Filtering with WHERE
Filter rows with WHERE — comparison operators and AND / OR
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Explanation
WHERE filters which rows a query returns.
sql
SELECT name, salary
FROM employees
WHERE salary > 80000;Comparison operators: =, != (or <>), <, >, <=, >=
Combining conditions:
AND— both conditions must be trueOR— at least one condition must be true
sql
SELECT *
FROM employees
WHERE department = 'Engineering' AND salary > 80000;Text values go in single quotes: WHERE department = 'Engineering'. Numbers don't need quotes: WHERE age > 18.
Examples
Filtering with AND
Returns engineers earning more than 80000
SELECT id, name, salary
FROM employees
WHERE department = 'Engineering'
AND salary > 80000;How well did you understand this?
Next in SQL & Databases
Sorting with ORDER BY