SQL - MODIFY COLUMN SQL ALTER TABLE Statement

Sometimes we need to change the data type of a column. To do this, we use the ALTER TABLE Modify Column command. For Oracle and MySQL, the SQL syntax for ALTER TABLE Modify Column is,

ALTER TABLE "table_name"
MODIFY "column_name" "New Data Type";

For SQL Server, the syntax is,

ALTER TABLE "table_name"
ALTER COLUMN "column_name" "New Data Type";

Let's look at the example. Assuming our starting point is the Customer table created in the CREATE TABLE section:

Table Customer

Column Name	Data Type
First_Name	char(50)
Last_Name	char(50)
Address	char(50)
City	char(50)
Country	char(25)
Birth_Date	datetime

Our goal is to alter the data type of the "Address" column to char(100). To do this, we key in:

MySQL: 

ALTER TABLE Customer MODIFY Address char(100);

Oracle: 

ALTER TABLE Customer MODIFY Address char(100);

SQL Server: 

ALTER TABLE Customer ALTER COLUMN Address char(100);

Resulting table structure:

Table Customer

Column Name	Data Type
First_Name	char(50)
Last_Name	char(50)
Address	char(100)
City	char(50)
Country	char(25)
Birth_Date	datetime

SHARES

Share

Pin it

Tweet

Share

Share

Share

Buffer

Print

About Mariano

I'm Ethan Mariano a software engineer by profession and reader/writter by passion.I have good understanding and knowledge of AngularJS, Database, javascript, web development, digital marketing and exploring other technologies related to Software development.