How Can I Delete Duplicate Rows In SQL Query?

by

How to remove duplicate rows in SQL query?

SQL remove duplicate rows with Common Table Expressions (CTE)

  1. With CTE ([Name],
  2. HOW (CHOOSE [name],
  3. ROW_NUMBER() ON (SECTION IN [name],
  4. ORDER BY id) AS DuplicateCount.
  5. DA [SampleDB]. [Boo]. [Employee])

How to remove duplicate rows in SQL?

Description: This tutorial demonstrates how to remove duplicate rows from a table in SQL Server. To remove duplicate rows from a table in SQL Server, follow these steps. Find duplicate rows using the GROUP BY clause or the ROW_NUMBER() function. Use the DELETE statement to remove duplicate rows.

How to remove duplicate rows?

If you want to remove all duplicate rows in a sheet, just hold down Ctrl + A to select the entire sheet. 2. On the Data tab, in the Data Tools group, click Remove Duplicates. Note. You can also use this function to remove rows with the same values ​​in some columns.

How to remove duplicate rows in SQL based on a column?

To remove duplicates from a result set, use the DISTINCT statement in the SELECT clause as follows: SELECT DISTINCT column1, column2, … FROM table1 If you use a column after the DISTINCT statement, the underlying system dataset use that column of column to evaluate for duplicates.

How to remove duplicate rows in SQL based on two columns?

The best way to remove duplicate rows from multiple columns is the simplest: add a UNIQUE index: ALTER IGNORE TABLE your_table ADD UNIQUE(field1, field2, field3) IGNORE above ensures that only the first row found is kept and the rest are removed.

How to select duplicate rows in SQL?

How to find duplicate values ​​in SQL

  1. Use the GROUP BY clause to group all rows based on the target columns, e.g. NOW. the columns you want to check for duplicate values.
  2. If you use the COUNT function in the HAVING clause to check if any of the groups have more than one entry, these will be duplicate values.

How do you randomly remove duplicate rows in a SQL query?

Alternative solutions are listed below:

  1. Remove duplicates of Row_Number. WITH CTE(Col1, Col2, Col3, DuplicateCount) AS (SELECT Col1, Col2, Col3, ROW_NUMBER() OVER (PARTITION BY Col1, Col2, Col3 ORDER BY Col1) AS DuplicateCount FROM MyTable) SELECT * FROM CTE WHERE DuplicateCount = 1.
  2. Remove duplicates with the After group.
Exit mobile version