text: create unique index pk_warehouse
   on warehouse(w_id);
  
  alter table warehouse add constraint
   primary key (w_id) constraint pk_warehouse;  
  
  create unique index pk_district
   on district(d_w_id, d_id);
  
  alter table district add constraint
   primary key (d_w_id, d_id) constraint pk_district;
  
  create unique index pk_customer
   on customer(c_w_id, c_d_id, c_id);
  
  alter table customer add constraint
   primary key (c_w_id, c_d_id, c_id) constraint pk_customer;
  
  create index ndx_customer_name 
   on customer (c_w_id, c_d_id, c_last, c_first);
  
  create unique index pk_oorder
   on oorder(o_w_id, o_d_id, o_id);
  
  alter table oorder add constraint
   primary key (o_w_id, o_d_id, o_id) constraint pk_oorder;
  
  create unique index ndx_oorder_carrier 
   on oorder (o_w_id, o_d_id, o_carrier_id, o_id);
   
  create unique index pk_new_order 
   on new_order(no_w_id, no_d_id, no_o_id);
  
  alter table new_order add constraint
   primary key (no_w_id, no_d_id, no_o_id) constraint pk_new_order;
  
  create unique index pk_order_line
   on order_line (ol_w_id, ol_d_id, ol_o_id, ol_number);
  
  alter table order_line add constraint
   primary key (ol_w_id, ol_d_id, ol_o_id, ol_number) constraint pk_order_line;
  
  create unique index pk_stock
   on stock (s_w_id, s_i_id);
  
  alter table stock add constraint
   primary key (s_w_id, s_i_id) constraint pk_stock;
  
  create unique index pk_item
   on item(i_id);
  
  alter table item add constraint
   primary key (i_id) constraint pk_item;
  
  create unique index pk_0order on oorder(o_w_id, o_d_id, o_c_id, o_id);
  