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SQL (Structured Query Language) starts simple—SELECT, FROM, WHERE—but its true power lies in advanced functions that enable complex analysis, transformations, and aggregations. This article explores some of the most powerful advanced SQL functions with practical use cases.
Purpose:
Perform calculations across a set of rows related to the current row, without collapsing the rows like GROUP BY.
Common Functions:
Purpose:
Create temporary named result sets for reuse within a query—especially helpful in breaking down complex queries.
Conditional logic helps categorize or create derived columns on the fly
4. CASE WHEN (Conditional Logic)
Purpose:
Apply if-else logic inside SQL queries
Advanced SQL functions transform SQL from a querying tool into an analytical powerhouse. By mastering these, you can:
- CASE WHEN (Conditional Logic) ## 1. Window Functions (Analytic Functions)
Purpose:
Perform calculations across a set of rows related to the current row, without collapsing the rows like GROUP BY.
Common Functions:
- ROW_NUMBER()
- RANK(), DENSE_RANK()
- LAG(), LEAD()
- SUM() OVER(...), AVG() OVER(...)
Purpose:
Create temporary named result sets for reuse within a query—especially helpful in breaking down complex queries.
Conditional logic helps categorize or create derived columns on the fly
4. CASE WHEN (Conditional Logic)
Purpose:
Apply if-else logic inside SQL queries
Advanced SQL functions transform SQL from a querying tool into an analytical powerhouse. By mastering these, you can:
- Write cleaner, more efficient queries
- Avoid complex application-side processing
- Gain deeper insights from raw data