How to Rename a Column in PL/SQL?

Renaming a column in PL/SQL is a fundamental operation in Oracle Database management. It enhances clarity, maintains consistency, or accommodates evolving data requirements.

Database administrators can ensure the data integrity and process of streamlining data manipulation by altering the column names. PL/SQL can provide the direct syntax for executing the renaming of the column operations within the Oracle database.

How to Rename a Column in PL/SQL

Renaming the column name in PL/SQL involved the ALTER TABLE statement for modifying the structure of the existing table. This enables the users to rename a column name without changing the datatype or other attributes of the existing column.

Syntax to rename a column in PL/SQL

ALTER TABLE table_name
RENAME COLUMN old_column_name TO new_column_name;

where,

• ALTER TABLE: Initiates the command to alter the structure of an existing table.
• table_name: Specifies the table containing the column to rename.
• RENAME COLUMN: Informs Oracle to change the name of a specific column in the specified table.
• old_column_name: Refers to the current name of the column.
• new_column_name: Refers to the new name you want to assign to the column.

Note: If you change the column name, it does not effect its data type or any other attributes. Be careful that any dependencies like views, procedures or triggers that may affect by change the column name and update accordingly.

Example of Renaming Column in PL/SQL

Example 1: Rename a column "Ename" to "Empname" in EMP table

Step 1: Create a table in PL/SQL. (Example: emp )

Step 2: Retrieve the table data before altering the column name in a table using the below syntax.

Select * from table_name;

Example:

Step 3: You can use the ALTER TABLE statement to altering the ENAME column to the EMPNAME by using the below syntax.

ALTER TABLE table_name
RENAME COLUMN old_column_name TO new_column_name;

Example:

Step 4: After altering, we query the emp table again to verifying the column name has been changed or not. The output will show the altered column ENAME to EMPNAME.

Output:

Example 2: Renaming the column "Sal" to "Salary" in the EMP table

Step 1: Create a table in PL/SQL. (Example: emp)

Step 2: Retrieve the table data before altering the column name in a table using the below syntax.

Select * from table_name;

Example:

Step 3: You can use the ALTER TABLE statement to rename the Sal column to the Salary by using the below syntax.

ALTER TABLE table_name
RENAME COLUMN old_column_name TO new_column_name;

Example:

Step 4: After altering, we query the emp table again to verifying the column name has been changed or not. The output will show the altered column SAL to SALARY.

Output:

Conclusion

In conclusion, renaming a column in PL/SQL is vital for enhancing database clarity, consistency, and adaptability within Oracle Database systems. By using the ALTER TABLE command effectively, database administrators can modify column names without compromising data integrity or disrupting operations.

Recently the PL/SQL robust features for manipulation of the data and modification of the schema enabled the seamless column renaming while maintaining the overall stability of the database system.