How to modify column name in oracle

In Oracle database, modifying column names is a common operation. When the table structure needs to be changed or the column names are inappropriate, we need to modify the column names. This article will describe how to modify column names through the ALTER TABLE statement.

1. View table structure

Before modifying the column name, we need to view the table structure to determine the column name that needs to be modified.

You can use the following statement to view the table structure:

DESC 表名;

Among them, DESC represents the abbreviation of describe, which is used to display the structure of the table.

After executing this statement, we can see the table structure, column names and other information. For example:

Name | Null | Type | 
---------------------
ID   | Y    | INT  |
Name | Y    | CHAR |
Age  | Y    | INT  |

This indicates that the table contains three columns, namely ID, Name, and Age.

2. Modify the column name

There are two ways to modify the column name:

(1) Use the ALTER TABLE statement

If We need to modify the table structure, and we can use the ALTER TABLE statement to modify the column names. The specific syntax is as follows:

ALTER TABLE 表名 RENAME COLUMN 原列名 TO 新列名;

For example, to change the Name column name in the table to Full_Name, you can execute the following statement:

ALTER TABLE 表名 RENAME COLUMN Name TO Full_Name;

After executing this statement, we can execute the DESC table name; statement again to confirm whether the column name has been modified successfully.

(2) Use the RENAME statement

If we only need to modify the column name without modifying the table structure, we can use the RENAME statement to directly modify the column name. The specific syntax is as follows:

RENAME COLUMN 表名.原列名 TO 新列名;

For example, to change the Name column name in the table to Full_Name, you can execute the following statement:

RENAME COLUMN 表名.Name TO Full_Name;

After executing this statement, we can use the DESC table name; statement Confirm whether the column name is modified successfully.

3. Notes

When modifying the column name, you need to pay attention to the following points:

(1) Modifying the column name may cause other dependencies on the Column-named objects are not working properly. Before modifying, you need to confirm whether the column name is called by other objects, and modify it accordingly if necessary.

(2) Only one column name can be modified. If you need to modify multiple column names, you need to execute ALTER TABLE statements or RENAME statements in sequence.

(3) Modifying the column name will not affect the data type and data itself.

Summary

Through the above steps, we can successfully modify the column names in the Oracle database. Whether through the ALTER TABLE or RENAME statement, you need to confirm whether the column name is called by other objects before modifying it, and note that only one column name can be modified.

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