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