Wiki Article · Cinematic

Window Function

Window function SQL ka ek advanced aur powerful feature hai jo har row ke saath ek computed value…

Overview

Window Function — Quick Facts

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Field: Detail

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Full Name: Window Function (SQL)

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Also Known As: Analytic Function, Windowed…

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Introduced In: SQL:2003 Standard

Topic 1

Infobox

📚 | Field | Detail | |-------|--------| | Full Name | Window Function (SQL) | | Also Known…

Topic 2

Kya Hai Window Function?

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Ranking — Har row ko uska rank…

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Running Total — Cumulative sum…

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Comparison — Current row ko…

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Moving Average — Last N rows ka…

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Real-Life Analogy — Classroom Rank Sheet

🎯 Imagine ek school ka classroom rank sheet: | Student | Marks | Rank |…

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GROUP BY vs Window Function

⭐ | Aspect | GROUP BY + Aggregate | Window Function |…

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OVER() Clause — The Heart

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Empty OVER() — SUM(amount) OVER()…

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PARTITION BY only — SUM(amount)…

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Full specification — PARTITION BY…

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Window Function Types

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Aggregate Window Functions — Wahi…

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Ranking Functions — Har row ko ek…

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Value Functions — Kisi specific…

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Query Execution Flow — Mermaid Diagram

🌟 `mermaid flowchart TD A["SQL Query Submitted"] --> B["FROM + JOIN — Tables Identify"] B…

Topic 8

PARTITION BY Explained

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Section A ke students ko unka rank…

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Section B ke students ko unka rank…

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Har partition independent hai — ek…

Topic 9

ORDER BY Inside OVER

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Without ORDER BY: SUM(amount)…

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With ORDER BY: SUM(amount)…

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Frame Specification — Sliding Window

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ROWS — Physical row count ke basis…

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RANGE — Value range ke basis par…

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GROUPS — Peer groups (same ORDER…

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Common Use Cases

🎯 | Use Case | Function(s) Used | Description |…

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Database Support Comparison

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Performance Considerations

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ORDER BY columns par index hona…

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PARTITION BY columns par index…

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Composite index (PARTITION BY…

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Bahut bada partition (millions of…

Topic 14

Enterprise Context

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Dashboard metrics — Running…

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KPI calculations — Employee…

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Financial reporting — Cumulative…

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De-duplication — ROW_NUMBER() se…

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Common Mistakes

🌟 1. WHERE Clause Me Window Function Use Karna Window function WHERE ke baad evaluate hoti…

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Interview Questions & Answers

🚀 Q1: Window Function aur GROUP BY me kya fark hai? A: GROUP BY multiple rows ko ek row me…

Topic 17

Glossary

📚 | Term | Meaning | |------|---------| | Window Function | SQL function jo OVER() clause…

Comparison

GROUP BY vs Window Function

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Row Behavior: Multiple rows → 1…

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Output Rows: Kam rows (grouped)

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Use Case: Summary report (total sales…

Comparison

Database Support Comparison

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ROW_NUMBER(): Yes

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RANK(): Yes

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DENSE_RANK(): Yes

Diagram

Visual Flow

📊 Diagram visualization — details in narration

Quiz — Question 1

Window Function ka sabse sahi definition kya hai?

Quick Quiz

Quiz — Question 2

Window Function ka 'Full Name' kya hai?

Complete! 🎉

Window Function Complete!

Aliens Wiki · HIEN · Cinematic Knowledge

✅

Window Function Complete

➡️

Window Function

Window Function — Quick Facts

Field: Detail

Full Name: Window Function (SQL)

Also Known As: Analytic Function, Windowed…

Introduced In: SQL:2003 Standard

Infobox

Kya Hai Window Function?

Ranking — Har row ko uska rank…

Running Total — Cumulative sum…

Comparison — Current row ko…

Moving Average — Last N rows ka…

Real-Life Analogy — Classroom Rank Sheet

GROUP BY vs Window Function

OVER() Clause — The Heart

Empty OVER() — SUM(amount) OVER()…

PARTITION BY only — SUM(amount)…

Full specification — PARTITION BY…

Window Function Types

Aggregate Window Functions — Wahi…

Ranking Functions — Har row ko ek…

Value Functions — Kisi specific…

Query Execution Flow — Mermaid Diagram

PARTITION BY Explained

Section A ke students ko unka rank…

Section B ke students ko unka rank…

Har partition independent hai — ek…

ORDER BY Inside OVER

Without ORDER BY: SUM(amount)…

With ORDER BY: SUM(amount)…

Frame Specification — Sliding Window

ROWS — Physical row count ke basis…

RANGE — Value range ke basis par…

GROUPS — Peer groups (same ORDER…

Common Use Cases

Database Support Comparison

Performance Considerations

ORDER BY columns par index hona…

PARTITION BY columns par index…

Composite index (PARTITION BY…

Bahut bada partition (millions of…

Enterprise Context

Dashboard metrics — Running…

KPI calculations — Employee…

Financial reporting — Cumulative…

De-duplication — ROW_NUMBER() se…

Common Mistakes

Interview Questions & Answers

Glossary

GROUP BY vs Window Function

Row Behavior: Multiple rows → 1…

Output Rows: Kam rows (grouped)

Use Case: Summary report (total sales…

Database Support Comparison

ROW_NUMBER(): Yes

RANK(): Yes

DENSE_RANK(): Yes

Visual Flow

See Also

SQL

Structured Query Language

Database

Relational Database

Query Optimization

Common Table Expression

Quiz — Question 1

Quiz — Question 2

Window Function Complete!

Window Function Complete

SQL