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This MySQL tutorial explains how to use the DELETE LIMIT statement in MySQL with syntax and examples. DescriptionThe MySQL DELETE LIMIT statement is used to delete records from a table in MySQL and limit the number of records deleted based on a limit value. SyntaxThe syntax for the DELETE LIMIT statement in MySQL is: DELETE FROM table [WHERE conditions] [ORDER BY expression [ ASC | DESC ]] LIMIT row_count; Parameters or ArgumentstableThe table that you wish to delete records from.WHERE conditionsOptional. The conditions that must be met for the records to be deleted.ORDER BY expressionOptional. It is used in the DELETE LIMIT statement so that you can order the results and target those records that you wish to delete.LIMIT row_countIt specifies a limited number of rows in the result set to delete based on row_count. For example, LIMIT 10 would delete the first 10 rows matching the delete criteria. This is where sort order matters so be sure to use an ORDER BY clause appropriately.Note
ExampleLet's look at how to use a DELETE statement with a LIMIT clause in MySQL. For example: DELETE FROM contacts WHERE website = 'TechOnTheNet.com' ORDER BY contact_id DESC LIMIT 2; This DELETE LIMIT example would delete the first 2 records from the contacts table where the website is 'TechOnTheNet.com'. Note that the results are sorted by contact_id in descending order so this means that the 2 largest contact_id values will be deleted by the DELETE LIMIT statement. If there are other records in the contacts table that have a website value of 'TechOnTheNet.com', they will not be deleted by the DELETE LIMIT statement in MySQL. If we wanted to delete the smallest contact_id values instead of the largest two, we could change the sort order as follows: DELETE FROM contacts WHERE website = 'TechOnTheNet.com' ORDER BY contact_id ASC LIMIT 2; Now the results would be sorted by contact_id in ascending order, so the first two smallest contact_id records that have a website of 'TechOnTheNet.com' would be deleted by this DELETE LIMIT statement. No other records would be affected. In this article, we are going to learn how we can update and delete data using Delete and Update statements. In my previous articles, we have learned how we can insert data using INSERT statement, and sort and filter data using WHERE and ORDER BY statements. To demonstrate UPDATE and DELETE statements, I have restored the sakila database on MySQL Server. We are going to use the film and language table of the sakila database. MySQL UPDATE StatementThe UPDATE is used to update the values of one or multiple columns of a table. The syntax is the following:
In this syntax, after the UPDATE keyword,
The Update statement has the following two modifiers:
Low_Priority modifierThe LOW_PRIORITY modifier is used when you want to delay the execution of the UPDATE query. When you specify the LOW_PRIORITY modifier, the query waits until all the SELECT queries are executed. The storage engines that use the table-level locking (Memory, MyISAM, and MERGE) can use this modifier. IGNORE modifierWhen we specify the IGNORE modifier in the update statement, the execution of the UPDATE statement continues even after it encounters an error. Suppose the UPDATE statement encounters an error that was raised due to unique constraint (duplicate value error) or data conversion errors. This one is helpful when you are running an UPDATE statement that changes the values of a large number of rows. Now, let us see some examples of the MySQL Update Statement. Example 1: Change the value of a single columnSuppose we want to change the rating from G to NC-17 of the movie title ACE GOLDFINGER. Execute the following query to view the current values of the rating column.
Query result:
Execute the following query to update values:
To verify that values have been updated, run the following query:
Query result:
As you can see, the rating has been changed. Example 2: Change the value of multiple columnsSuppose we want to change the replacement cost from 12.99 to 15 and length from 48 to 50 of the movie title AGENT TRUMAN. To change the values, execute the following query to view the current data.
Query Result:
The new value of the replacement_cost column will be 15, and the value of the length column will be 200. To update the values, run the following query:
To verify that values have been updated, run the following query:
Query result:
As you can see, the values have been changed. Example 3: Change the value using sub-queryIn the UPDATE statement, we can also change the value of the column based on the output of the sub-query. Suppose we want to change the value of the language_id of a movie title AGENT TRUMAN without using a static value. Execute the following query to view the current value of the language_id column.
The output is the following:
As you can see, the value of the language_id column is 1 (English). The new value of the language_id column is 2 (Italian). To do that, execute the following query.
To verify that the language_id has been changed, run the below query.
Output:
MySQL DELETE StatementThe MySQL DELETE statement is used to remove the data from the MySQL table. The syntax is the following:
In the syntax,
Important notes about DELETE statements
The DELETE statement has the following modifiers:
Low_Priority modifierThe LOW_PRIORITY modifier is used when you want to delay the execution of the DELETE query. When you specify the LOW_PRIORITY modifier, the query waits until all the SELECT queries are executed. QUICK ModifierThe QUICK modifier can be used in MyISAM tables. When this modifier is used, the index leaves do not merge by the storage engine. This helps to improve the speed of the delete operation. IGNORE modifierWhen we specify the IGNORE modifier in the update statement, the execution of the DELETE statement continues even after it encounters an error. This one is helpful when you are running a DELETE statement that changes the values of a large number of rows. Now, let us see a few examples of the DELETE statement. Example 1: Delete all the records from the tableSuppose, we want to delete all the data from the language table. To do that, execute the following query: The output will show the number of records deleted.
Example 2: Delete a specific record from a tableSuppose we want to delete a movie title whose name is ‘AGENT TRUMAN’ from the film table. To do that, execute the following query:
The output will show the number of records deleted.
Example 3: Delete the rows using LIMITSuppose we want to limit the number of records to be deleted from the table. To do that, we can use the LIMIT clause. This method is useful when we want to perform the delete operation in batches. Suppose we want to delete only 50 records from the film table. To do that, execute the following query:
The following is the output:
SummaryIn this article, we have learned about UPDATE and DELETE statements of MySQL and the various use cases and examples of it. Table of contents
Nisarg Upadhyay is a SQL Server Database Administrator and Microsoft certified professional who has more than 8 years of experience with SQL Server administration and 2 years with Oracle 10g database administration. He has expertise in database design, performance tuning, backup and recovery, HA and DR setup, database migrations and upgrades. He has completed the B.Tech from Ganpat University. He can be reached on Why delete is not working in MySQL?Solution. By default, MySQL workbench is started in safe mode, and can't update or delete, without a “WHERE” condition, see the error message. To fix it, in menu, selects “Edit” -> “Preferences” -> “SQL Queries”, uncheck the “Safe Updates” checkbox. Done, try reconnect and issue the delete command again.
How do I turn off safe mode in SQL?You can use the SET statement to disable the safe update as shown below: SET SQL_SAFE_UPDATES = 0; Now you should be able to execute an UPDATE or DELETE statement without a WHERE clause.
Is deletion possible in MySQL?You can specify multiple tables in a DELETE statement to delete rows from one or more tables depending on the condition in the WHERE clause. You cannot use ORDER BY or LIMIT in a multiple-table DELETE .
Why we use delete command in MySQL?The DELETE statement is used to delete existing records in a table.
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