Introduction
Occasionally, we might want to rename our table to something more appropriate. To rename the table, we can use ALTER TABLE for this purpose.
Syntax(Oracle,MySQL,MariaDB):
ALTER TABLE table_name
RENAME TO new_table_name; |
Columns can also be given new name with the use of ALTER TABLE.
Syntax(MySQL, Oracle):
ALTER TABLE table_name
RENAME COLUMN old_name TO new_name; |
Syntax(MariaDB):
ALTER TABLE table_name
CHANGE COLUMN old_name TO new_name; ExampleConsider the following table: ID | NAME | AGE | STATE | EMAIL | ID_NUMBER | COUNTRY | 1 | Pari | 24 | Delhi | pari@example.com | NULL | India | 2 | Mira | 28 | Kerala | mira@example.com | NULL | India | 3 | Riya | 19 | Delhi | riya@example.com | NULL | India |
To rename ID column(The first column) to user_id the following syntax can be used: ALTER TABLE ID
RENAME COLUMN id TO user_id; |
Output: user_id | NAME | AGE | STATE | EMAIL | ID_NUMBER | COUNTRY | 1 | Pari | 24 | Delhi | pari@example.com | NULL | India | 2 | Mira | 28 | Kerala | mira@example.com | NULL | India | 3 | Riya | 19 | Delhi | riya@example.com | NULL | India |
When renaming a column in a table, be cautious. You run the risk of destroying database dependencies when you use ALTER TABLE to rename columns. Instead of using ALTER TABLE to rename a column, a database refactoring tool will take care of all the dependents and update them with the new column name. If you have a tiny database you may not need to worry, but it is crucial to keep in mind. ConclusionIn this article, you have learned how to use ALTER TABLE to add a column and rename a column in a table.
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