Add unique constraints : Unique « Constraints « Oracle PL / SQL






Add unique constraints

   
SQL>
SQL>
SQL> set echo off
SQL> create table emp(
  2           emp_id            integer     primary key using index (create index pk_idx on emp(emp_id) )
  3          ,lastname               varchar2(20)   constraint lastname_create_nn not null
  4          ,firstname              varchar2(15)   constraint firstname_create_nn not null
  5          ,midinit                varchar2(1)
  6          ,street                 varchar2(30)
  7          ,city                   varchar2(20)
  8          ,state                  varchar2(2)
  9          ,zip                    varchar2(5)
 10          ,shortZipCode           varchar2(4)
 11          ,area_code              varchar2(3)
 12          ,phone                  varchar2(8)
 13          ,company_name           varchar2(50)
 14          ,constraint unique_emp_phone unique(phone) using index (create index emp_phone_u_idx on emp(phone))
 15          );

Table created.

SQL>
SQL> select index_name, table_name, column_name from user_ind_columns where table_name = 'emp';

no rows selected

SQL>
SQL> select constraint_name, table_name, column_name from user_cons_columns where table_name = 'emp';

no rows selected

SQL>
SQL> drop table emp             cascade constraints;

Table dropped.

   
    
    
  








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