[Solved] Difference between Alter and Update SQL
I am busy studying MySQL and I understand that update is used to update a record or row in a table. So what does alter do that is so different? Seems like they are the same.
Thanks, any help will be appreciated.
Solution #1:
ALTER
is a DDL (Data Definition Language) statement. Whereas UPDATE
is a DML (Data Manipulation Language) statement. ALTER
is used to update the structure of the table (add/remove field/index etc). Whereas UPDATE
is used to update data.
Solution #2:
The ALTER
changes the table in the database, you can add or remove columns, etc. But it does not change data (except in the dropped or added columns of course).
While the UPDATE
changes the rows in the table, and leaves the table unchanged.
Solution #3:
ALTER
is used to change things like table structures or stored procs, otherwise known as DDL statements.
ALTER table MyTable
ADD MyNewColumn VARCHAR(100)
OR
ALTER PROC dbo.MyStoredProc
Solution #4:
Alter command is a data definition language
Update command is a data manipulation language
Alter example- table structure, table name, sp, functions
Update example-change database in a row or column etc
Alter command make changes in table structure.
Update command make changes with inside the table
Alter command is used to add, delete modify the attributes of the table in the database
Update command is used to update existing record in a database