SQL alert modifies a table or adds columns

SQL alert commands are used to modify data table names, add columns, delete columns, modify field data types, and so on. All right, let's take a look at the example below.

Database ALTER TABLE syntax
To add a column to a table, use the following syntax:

ALTER TABLE table_name  ADD column_name datatype

Let's look at an example of an additional example:

Alter TABLE Tname  alter COLUMN data year

This adds a year field to the Tname table that is listed as the data type

Above is the syntax for adding columns to the table. Let's take a look at the Delete column. Drop Columns column_name

ALTER TABLE table_name DROP COLUMN column_name

To see a delete column instance.

ALTER TABLE Persons DROP COLUMN dateOfBirth

To modify the field type:

ALTER COLUMN column_name datatype _id ORDER BY w_support Desc

p_id  LastName   FirstName  
1       Hansen      Ola        
2       Svendson    Tove       
3      Pettersen     Kari      STORGT Stavanger

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