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Databases & SQL vocabulary · SQL Statements and Queries

Window function

Meaning in databases & SQL, with examples

nounAdvanced term

In databases & SQL, window function means: A SQL function that calculates a value across a set of related rows, such as a running total or a rank, while still returning every individual row.

In Turkish: pencere fonksiyonu, analitik fonksiyon

How it is used

Written with OVER, often with PARTITION BY and ORDER BY: ROW_NUMBER() OVER (PARTITION BY customer_id ORDER BY created_at). Common ones are ROW_NUMBER, RANK, LAG, LEAD and SUM OVER. Unlike GROUP BY, rows are not collapsed. Oracle calls them analytic functions.

Example sentences

  1. Use a window function to get each customer's most recent order.

  2. The running balance column is calculated with a window function over the transactions.

Common collocations

  • window function
  • OVER (PARTITION BY ...)
  • ROW_NUMBER()
  • running total
  • aggregate functionA SQL function that takes many rows and returns a single value from them, such as COUNT, SUM, AVG, MIN or MAX.
  • GROUP BYThe SQL clause that puts rows with the same values into groups so that a total, count or average can be calculated for each group.
  • ORDER BYThe SQL clause that sorts the rows of a result by one or more columns, in ascending (ASC) or descending (DESC) order.
  • CTECommon table expression: a named temporary result defined with WITH at the start of a query, which the main query can then use like a table.

This word in other fields

The same English word can have a different meaning in another field:

More terms: SQL Statements and Queries

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