anton
53 lines
987 B
SQL
53 lines
987 B
SQL
/*Задача 1: Какой будет порядок выполнения у запросов?
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SELECT name, age
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FROM users
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WHERE is_active = true AND country = 'Canada'
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ORDER BY age
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LIMIT 3;
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*/
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1. FROM users
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2. WHERE is_active = true AND country = 'Canada'
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3. SELECT name, age
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4. ORDER BY age
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5. LIMIT 3
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/*
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SELECT country, COUNT(*) AS active_users
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FROM users
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WHERE is_active = true
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GROUP BY country
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HAVING COUNT(*) > 1;
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*/
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1. FROM users
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2. WHERE is_active = true
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3. GROUP BY country
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4. HAVING COUNT(*) > 1
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5. SELECT country, COUNT(*) AS active_users
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/*
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SELECT country, AVG(age) AS avg_age
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FROM users
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GROUP BY country
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HAVING COUNT(*) >= 3 AND AVG(age) > 25;
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*/
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1. FROM users
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2. GROUP BY country
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3. HAVING COUNT(*) >= 3 AND AVG(age) > 25
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4. SELECT country, AVG(age) AS avg_age
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/*
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SELECT name, age
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FROM users
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WHERE is_active = false AND age > 30
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ORDER BY name;
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*/
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1. FROM users
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2. WHERE is_active = false AND age > 30
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3. SELECT name, age
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4. ORDER BY name |