How do you modify an existing column's data type in a table using SQL?
How do you modify an existing column's data type in a table using SQL?
207
30-Aug-2023
Updated on 31-Aug-2023
Aryan Kumar
31-Aug-2023To modify an existing column's data type in a table using SQL, you can use the ALTER TABLE statement. The syntax for the ALTER TABLE statement is:
SQL
The
table_nameis the name of the table that contains the column that you want to modify. Thecolumn_nameis the name of the column that you want to modify. Thedata_typeis the new data type that you want to assign to the column.For example, the following statement will modify the data type of the
agecolumn in thecustomerstable tovarchar(255):SQL
It is important to note that when you modify the data type of a column, any existing data in the column will be converted to the new data type. If the new data type is smaller than the old data type, any data that is not compatible with the new data type will be truncated.
Here are some things to keep in mind when modifying the data type of a column: