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SQL में रिपोर्टिंग

Tyler Pernes

Learning & Development Consultant

लक्ष्य रिपोर्ट

जनसांख्यिकीय समूह के अनुसार स्वर्ण पदक
(केवल पश्चिमी यूरोपीय देश)
+----------+--------------------+-------+
| season   |  demographic_group | golds |
|----------+--------------------+-------|
| Winter   | Male Age 26+       | 13    |
| Winter   | Female Age 26+     | 8     |
| Summer   | Male Age 13-25     | 7     |
| Summer   | Female Age 13-25   | 6     |
| Winter   | Male Age 13-25     | 4     |
| Summer   | Male Age 26+       | 4     |
| Winter   | Female Age 13-25   | 4     |
| Summer   | Female Age 26+     | 2     |
+----------+--------------------+-------+

प्रासंगिक टेबल्स

विकल्प A: पहले JOIN, फिर UNION

Step 1: ऊपर की क्वेरी JOIN के साथ सेटअप करें

SELECT 
    athlete_id, 
    gender, 
    age, 
    gold  
FROM summer_games AS sg
JOIN athletes AS a 
ON sg.athlete_id = a.id;

Query ran successfully!

विकल्प A: पहले JOIN, फिर UNION

Step 2: नीचे की क्वेरी सेट करें + दोनों को UNION करें

SELECT 
    athlete_id, 
    gender, 
    age, 
    gold  
FROM summer_games AS sg
JOIN athletes AS a 
ON sg.athlete_id = a.id
UNION ALL
SELECT 
    athlete_id, 
    gender, 
    age, 
    gold  
FROM winter_games AS wg
JOIN athletes AS a 
ON wg.athlete_id = a.id;

विकल्प B: पहले UNION, फिर JOIN

Step 1: प्रारंभिक UNION बनाएँ

SELECT 
    athlete_id, 
    gold  
FROM summer_games AS sg
UNION
SELECT 
    athlete_id, 
    gold  
FROM winter_games AS wg;

विकल्प B: पहले UNION, फिर JOIN

Step 2: सबक्वेरी में बदलें + JOIN करें

SELECT 
    athlete_id, 
    gender, 
    age, 
    gold  
FROM
    (SELECT 
         athlete_id, 
         gold  
    FROM summer_games AS sg
    UNION ALL
    SELECT athlete_id, gold  
    FROM winter_games AS wg) AS g
JOIN athletes AS a 
ON g.athlete_id = a.id;

तुलना

Option A

SELECT 
    athlete_id, 
    gender, 
    age, 
    gold  
FROM summer_games AS sg
JOIN athletes AS a 
ON sg.athlete_id = a.id
UNION ALL
SELECT 
    athlete_id, 
    gender, 
    age, 
    gold  
FROM winter_games AS wg
JOIN athletes AS a 
ON wg.athlete_id = a.id;

Option B

SELECT 
    athlete_id, 
    gender, 
    age, 
    gold  
FROM
    (SELECT 
         athlete_id, 
         gold  
    FROM summer_games AS sg
    UNION ALL
    SELECT athlete_id, gold  
    FROM winter_games AS wg) AS g
JOIN athletes AS a 
ON g.athlete_id = a.id;

मुख्य बातें

एक ही रिपोर्ट बनाने के कई तरीके
स्टेप-बाय-स्टेप = ट्रबलशूट करना आसान

क्वेरी समय!

SQL में रिपोर्टिंग