![]() This article explores the different methods to remove duplicate data from the SQL table. We need to follow specific methods to clean up duplicate data. It is a best practice as well to use the relevant keys, constrains to eliminate the possibility of duplicate rows however if we have duplicate rows already in the table. Suppose your SQL table contains duplicate rows and you want to remove those duplicate rows. We might also get these data in intermediate tables in data import, and we want to remove duplicate rows before actually inserting them in the production tables. Even we follow the best practices, and we might face issues such as duplicate rows. For example, a table should have primary keys, identity columns, clustered and non-clustered indexes, constraints to ensure data integrity and performance. We should follow certain best practices while designing objects in SQL Server. I hope you enjoyed this article and best of luck on your SQL journey.This article explains the process of performing SQL delete activity for duplicate rows from a SQL table. If you want to delete all records from the table then you can use this syntax. WHERE column_name IN (value 1, value 2, value 3, etc.) WHERE column_name BETWEEN value 1 AND value 2 Īnother way to delete multiple rows is to use the IN operator. If you wanted to delete a number of rows within a range, you can use the AND operator with the BETWEEN operator. There are a few ways to delete multiple rows in a table. If you want to delete one row from the table, then you have to specify a condition. This is the basic syntax for using the DELETE query: DELETE FROM table_name In this article, we learned about the different ways to delete information from a SQL table. In order to delete all of the cats from our cats table, then we would use this code. ![]() If you want to delete all of the information from your table, then you would use this syntax: DELETE FROM table_name #Sql studio manager table multiple delete how to#How to delete all records in the table in SQL Our DELETE query was successful, because those four cats are no longer present in the table. This is what the new result would look like: WHERE name IN ("Lucy","Stella","Max","Tiger") We need to specify the column and use the IN operator to list the names we want deleted. In this example, I want to delete the names of Lucy, Stella, Max and Tiger from our original cats table here: We can specify which names to delete from the cats table using the IN operator. How to delete multiple rows using the IN operator in SQL The ids of 4-7 have been successfully deleted. We can see that rows 1-3 and 8-10 are left in our table. This is the result from that DELETE query: Here is the syntax for that: DELETE FROM cats In this example, we want to delete rows with ids of 4-7 inclusive. If we wanted to delete a number of rows within a range, we can use the AND operator with the BETWEEN operator. How to delete multiple rows using the BETWEEN operator with the AND operator in SQL Now the cats table is only showing the female cats. If we wanted to delete the rows with just the male cats, then we can use the gender="M" condition. One way we can delete multiple rows from our cats table is to change the condition from id to gender. How to Delete multiple rows from a table in SQL We can see that our DELETE query worked because Loki's information is no longer there. This is what the new cats table looks like: Here is the complete syntax to delete Loki's row: DELETE FROM cats In the second line, we are going to specify which row by using the id=8 after the WHERE clause. The first line of the DELETE query would look like this: DELETE FROM cats We want to delete the row with the id of 8 which is Loki's row. The columns would be id, name and gender. In this example, we have a table called cats that currently has ten rows in it. ![]() WHERE condition of which row(s) to delete This is the basic syntax for using the the DELETE query: DELETE FROM table_name I will also show you how to delete multiple rows from a table at once. ![]() In the article, I will walk you through how to use the DELETE query and WHERE clause to delete rows. In SQL, you can delete a row in a table by using the DELETE query and the WHERE clause. ![]()
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