![]() Finding duplicate values in a table with a unique indexįROM TableA a, (SELECT ID, (SELECT MAX(Value) FROM TableA i WHERE o.Value=i.Value GROUP BY Value HAVING o.ID 1 To accomplish our tasks, we need a test environment which we create with the Removing duplicates rows from a SQL Server table with a unique index Test Environment Setup In this scenario, the ROW_NUMBER() function canīe used with a common table expression (CTE) to sort the data then delete theĬheck out the examples below to get real world examples on how to delete duplicate Table without a Unique Index - For tables without a unique index, it isĪ bit more challenging.Identification can be performed with self-joins, ordering theĭata by the max value, using the RANK function or using NOT IN logic. To use the index to order identify the duplicate data then remove the duplicate Table with Unique Index - For tables with a unique index, you have the opportunity.In SQL Server there are a number of ways toĪddress duplicate records in a table based on the specific circumstances such as: Withĭuplicate data it is possible for orders to be processed numerous times, have inaccurate How to remove duplicate rows in a SQL Server tableĭuplicate records in a SQL Server table can be a very serious issue. Indexes and contains duplicate rows which should be removed. The second case is that table does not have a primary key or any unique.The first case is when a SQL Server table has a primary key (or unique index)Īnd one of the columns contains duplicate values which should be removed. ![]()
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