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The update and delete commands in SQL are used to change the data stored in a table. The update command substitutes a row of the current row with a row from another row from the same table. The delete command simply deletes an entire row from the table. In this article, you will learn about how these two commands work and their differences. For example, if you want to add 100 rows of data to all of your tables in SQL Server, then use the following code: DELETE FROM "table1" UPDATE "table2" SET "col3" = "100".

If your database is using a single chain to store inserts and updates, then update has no overhead. However, with a multi-threaded database, update incurs the overhead of grouping all the updates for each insertion into one lock record. Insertion records remain on the list of updates until they are completed.Insertion is inserting a new key and update is updating the value of an existing key. If that is the case (a very common case) , update would be faster than insertion because update involves an indexed lookup and changing an existing value without touching the index.

SQL is a programming language that is used to build applications and databases. The delete command in SQL deletes all rows from a table or from a specific record. It can be used to remove data from the table for auditing purposes, update the records by deleting them and creating new ones with different values, and move the records to another table or spreadsheet The delete command in SQL can also be used with REPLACE function to replace an existing value with a new one.

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