create table currencies_new(id integer not null primary key, name varchar not null, position varchar not null, has_gap integer not null);
insert into currencies_new(id, name, position, has_gap) select id, name, position, has_gap from currencies;
drop table currencies;
alter table currencies_new rename to currencies;
create table currencies_new(id integer not null primary key, name varchar not null, position varchar not null, has_gap integer not null);
insert into currencies_new(id, name, position, has_gap) select id, name, position, has_gap from currencies;
drop table currencies;
alter table currencies_new rename to currencies;