関連ワード:  alter table postgres change column type    postgres alter table change column type not null    postgres alter table change column type default value    alter table change column type postgres example    postgres alter table change column type using    postgres alter table change column type to serial    postgresql alter table change column type to timestamp with timezone    postgresql alter table change column type varchar length    postgresql alter table change column type serial    postgresql alter table change column type not null  
結果 : alter table postgres change column type