text: create table ordem_servico (
  	id bigserial not null,
  	cliente_id bigint not null,
  	descricao text not null,
  	preco decimal(10,2) not null,
  	status varchar(20) not null,
  	data_abertura timestamp not null,
  	data_modificacao timestamp,
  	data_finalizacao timestamp,
  	
  	primary key (id)
  );
  
  alter table ordem_servico add constraint fk_ordem_servico_client
  foreign key (cliente_id) references cliente (id);