Answers for "alter table with default value"

add column table sql default value

ALTER TABLE users
ADD visit_number INT DEFAULT 0;

default number in sql

//Sql Server

//Add a table 
ALTER TABLE clients ADD Points INT DEFAULT 0
//Edit an existing table
ALTER TABLE clients ADD CONSTRAINT points DEFAULT 0 FOR Points

add column alter table default value

ALTER TABLE PERSON
ADD IS_ACTIVE VARCHAR2(1) DEFAULT 'N' NOT NULL