Difference between revisions of "Alter & Drop"
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ALTER TABLE Persons | ALTER TABLE Persons | ||
| − | ADD | + | ADD DateOfBirth date |
</syntaxhighlight> | </syntaxhighlight> | ||
Revision as of 13:22, 24 December 2016
Adding a Field
To add a column in a table, use the following syntax:
ALTER TABLE table_name
ADD column_name datatype
Example:
ALTER TABLE Persons
ADD DateOfBirth date
Deleting a Field
Next, we want to delete the column named "DateOfBirth" in the "Persons" table.
We use the following SQL statement:
ALTER TABLE Persons
DROP COLUMN DateOfBirth
Change Data Type
Now we want to change the data type of the column named "DateOfBirth" in the "Persons" table.
We use the following SQL statement:
ALTER TABLE Persons
ALTER COLUMN DateOfBirth year
