how to set default value in sql create table code example

Example 1: set default column value sql

Name Varchar(255) default "Fred"

Example 2: sql default

Sets a default value for a column;
Example 1 (MySQL): Creates a new table called Products which has a
name column with a default value of ‘Placeholder Name’ and an available_
from column with a default value of today’s date.
CREATE TABLE products (
id int,
name varchar(255) DEFAULT 'Placeholder Name',
available_from date DEFAULT GETDATE()
);
Example 2 (MySQL): The same as above, but editing an existing table.
ALTER TABLE products
ALTER name SET DEFAULT 'Placeholder Name',
ALTER available_from SET DEFAULT GETDATE();