You can change the table structure with the ALTER TABLE command. You
may use ALTER TABLE to change the table by adding, changing or deleting a
column in the table.
Table: Employee
| EmployeeID |
FirstName |
LastName |
Street |
City |
State |
Zipcode |
Phone |
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You can use the following SQL statement add Street2 field to the
Employee table.
ALTER
TABLE Employee ADD COLUMN Street2 CHAR
(30)
After executing the above command, the Employee table will looks like
the following table.
Table: Employee
| EmployeeID |
FirstName |
LastName |
Street |
Street2 |
City |
State |
Zipcode |
Phone |
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Besides adding column, you can also use ALTER TABLE to remove field
from a table. You can use the following SQL statement to remove Phone field
from Employee table.
ALTER
TABLE Employee DROP COLUMN
Phone
After executing the above SQL statement, the Employee table will
looks like the following.
Table: Employee
| EmployeeID |
FirstName |
LastName |
Street |
Street2 |
City |
State |
Zipcode |
| |
|
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.
