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SQL में रिपोर्टिंग

Tyler Pernes

Learning & Development Consultant

अध्याय का लक्ष्य

पूछने वाले प्रश्न

किन tables से डेटा लेना है?
tables को कैसे combine करें?
कौन से fields बनाने हैं?
कौन से filters शामिल हों?
कोई ordering या limiting चाहिए?

परिदृश्य

Gold Medals by Demographic Group
(Western European Countries Only)
+----------+--------------------+-------+
| 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     |
+----------+--------------------+-------+

1 - हमें किन tables से डेटा लेना है?

2 - tables को कैसे combine करें?

3 - कौन से fields बनाने हैं?

+----------+--------------------+-------+
| 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     |
+----------+--------------------+-------+

season - static string
demographic_group - conditional
golds - SUM()

4 - कौन से filters शामिल हों?

Gold Medals by Demographic Group
(Western European Countries Only)
+----------+--------------------+-------+
| 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     |
+----------+--------------------+-------+

WHERE या HAVING?
Dimension पर फ़िल्टर = WHERE

5 - कोई ordering या limiting चाहिए?

Gold Medals by Demographic Group
(Western European Countries Only)
+----------+--------------------+-------+
| 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     |
+----------+--------------------+-------+

LIMIT की ज़रूरत नहीं
golds के आधार पर descending क्रम में sort करें

अभ्यास करते हैं!

SQL में रिपोर्टिंग