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3 Οκτ 2008 · GROUP BY has a very specific meaning that is distinct (heh) from the DISTINCT function. GROUP BY causes the query results to be grouped using the chosen expression, aggregate functions can then be applied, and these will act on each group, rather than the entire resultset.
15 Μαρ 2014 · Distinct will not work fine with multi column. though given distinct on single column but it gives the unique combination of specified columns. So, Group by gives the unique records and can do aggregates too.
29 Αυγ 2024 · In this article, we’ve explored the differences between the GROUP BY and DISTINCT clauses in SQL. GROUP BY is ideal for aggregating data with summary functions, whereas DISTINCT is useful for filtering out duplicate rows.
14 Ιαν 2017 · This article compares the efficiency of two methods of grouping data: SELECT DISTINCT vs GROUP BY. It is the ninth in a series of articles discussing various tests done to compare the efficiency of different approaches to coding.
16 Μαρ 2022 · The GROUP BY and DISTINCT clauses can both be used to generate identical results. But which one is faster in Access? And--more importantly--why?
The GROUP BY clause in Access combines records with identical values in the specified field list into a single record. A summary value is created for each record if you include an SQL aggregate function , such as Sum or Count, in the SELECT statement. Syntax. SELECT fieldlist. FROM table. WHERE criteria. [GROUP BY groupfieldlist]
The outcome of DISTINCT is exactly the same as GROUP BY if you only try to find the unique values, but GROUP BY can be used together with other Aggregate Functions such as COUNT, SUM, AVERAGE. In terms of performance, they should be the same or nearly the same. Example 1 – Select one field with SELECT DISTINCT.
