command oreders solve

2026-01-16 12:31:08 +03:00
parent 0dca45f922
commit d7435d1e10
1 changed files with 53 additions and 0 deletions
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 /*Задача 1: Какой будет порядок выполнения у запросов?
 SELECT name, age
 FROM users
 WHERE is_active = true AND country = 'Canada'
 ORDER BY age
 LIMIT 3;
 */
 1. FROM users
 2. WHERE is_active = true AND country = 'Canada'
 3. SELECT name, age
 4. ORDER BY age
 5. LIMIT 3
 /*
 SELECT country, COUNT(*) AS active_users
 FROM users
 WHERE is_active = true
 GROUP BY country
 HAVING COUNT(*) > 1;
 */
 1. FROM users
 2. WHERE is_active = true
 3. GROUP BY country
 4. HAVING COUNT(*) > 1
 5. SELECT country, COUNT(*) AS active_users
 /*
 SELECT country, AVG(age) AS avg_age
 FROM users
 GROUP BY country
 HAVING COUNT(*) >= 3 AND AVG(age) > 25;
 */
 1. FROM users
 2. GROUP BY country
 3. HAVING COUNT(*) >= 3 AND AVG(age) > 25
 4. SELECT country, AVG(age) AS avg_age
 /*
 SELECT name, age
 FROM users
 WHERE is_active = false AND age > 30
 ORDER BY name;
 */
  1. FROM users
  2. WHERE is_active = false AND age > 30
  3. SELECT name, age
  4. ORDER BY name