Check out example codes for "set default value sql". It will help you in understanding the concepts better.

Code Example 1

Name Varchar(255) default "Fred"

Code Example 2

ALTER TABLE "name_table" ALTER "name_column" 
SET DEFAULT value_default;

Code Example 3

CREATE TABLE Persons
(

    ID int NOT NULL,

   
LastName varchar(255) NOT NULL,

   
FirstName varchar(255),

   
Age int,

   
City varchar(255) DEFAULT 'Sandnes'

);

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