From e1c82fcc39df131ef6fe6faf24cf64184f959d74 Mon Sep 17 00:00:00 2001 From: AdityaTharunJ Date: Fri, 29 May 2026 22:15:30 +0530 Subject: [PATCH] Refactor SQL queries to include GROUP BY and counts --- SQL Deep Dive/Group By/questions.sql | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) diff --git a/SQL Deep Dive/Group By/questions.sql b/SQL Deep Dive/Group By/questions.sql index cd0c9d5..aabba01 100644 --- a/SQL Deep Dive/Group By/questions.sql +++ b/SQL Deep Dive/Group By/questions.sql @@ -4,16 +4,20 @@ * Table: Employees */ -SELECT e.emp_no -FROM employees as e +SELECT hire_date, count(emp_no) +FROM employees GROUP BY hire_date +ORDER BY "amount" asc;l /* * Show me all the employees, hired after 1991 and count the amount of positions they've had * Database: Employees */ -SELECT e.emp_no -FROM employees as e +SELECT e.emp_no, count(t.titles) as "Amount of titles" +FROM employees as e JOIN titles as t USING(emp_no) +WHERE EXTRACT (YEAR FROM e.hire_date) > 1991 +GROUP BY e.emp_no +ORDER BY e.emp_no; /* @@ -21,5 +25,9 @@ FROM employees as e * Database: Employees */ -SELECT e.emp_no +SELECT e.emp_no, de.from_date, de.to_date FROM employees as e +JOIN dept_emp as de USING(emp_no) +WHERE de.dept_no = 'd005' +GROUP BY e.emp_no, de.from_date, de.to_date +ORDER BY e.emp_no, de.to_date;