Alter table add column and set default value in MySQL

Question

Is there a way to add a new column and set its default value in MySQL? When I run this command I get a syntax error:

ALTER TABLE tableName ADD newColumn varchar(20) SET DEFAULT 'test';

The documentation I've found doesn't really help me.

Answer 1

SET不是必需的：

ALTER TABLE tableName ADD newColumn varchar(20) DEFAULT 'test';

Answer 2

try this

ALTER TABLE tableName ADD COLUMN newColumn VARCHAR(20) DEFAULT 'test';