![]() Of course, to use the DELETE command you need DELETE permission for that table. Removing rows in another table can also trigger DELETE. It can be executed for any row change or when all rows are removed. A trigger can be called before, after, or instead of the DELETE operation. If you remove the last record in the table with ID=20 and then add a new record, this record will have ID=21 – even though the record immediately before it will be ID=19.ĭELETE can be executed by triggers. Every deleted row is locked, so it will require a lot of locks if you’re working in a large table.ĭELETE also keeps the auto-increment ID in the table. However, DELETE uses a row lock during execution and can be rolled back. DELETE returns the number of rows removed from the table. It can remove one, some, or all rows in a table. If you don’t want to remove table structure or you’re only deleting specific rows, use the DELETE command. Now the table product only has records with prices higher than $2.90: id ![]() … deletes only the records for milk and sugar, because their prices are lower than $2.90. After this query, the table product will be empty. … removes all the data in the table product. If you want to remove specific records, use WHERE with filtering conditions, as in the second example. ![]() Notice that there aren’t any column names in this syntax you’re removing all records, not the data in selected columns. If you’d like to remove all records from a given table, use DELETE FROM followed by the table name. Or you can delete a group of records using the WHERE clause: You can delete all records with the syntax: It is used only for deleting data from a table, not to remove the table from the database. ![]() This command removes records from a table. DELETE is a DML (Data Manipulation Language) command. ![]()
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