38 lines
454 B
Markdown
38 lines
454 B
Markdown
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---
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tags:
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- Programming_Languages
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- Databases
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- sql
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---
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# SQL Aggregate functions
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## Count return with custom variable
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````sql
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SELECT COUNT(*) AS total_sales
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FROM SALES
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````
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## Sum
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````sql
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SELECT SUM(price) as total_value
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FROM sales
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````
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## Average
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````sql
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SELECT AVG(price) as average_income
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FROM sales
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````
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## Applying aggregate function with sorting applied
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````sql
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SELECT COUNT(*) AS total_sales
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FROM sales
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GROUP BY employee_id
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````
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