count distinct column value : COUNT « Aggregate Functions « Oracle PL / SQL






  1. Oracle PL / SQL
  2. Aggregate Functions
  3. COUNT

count distinct column value

   

create table employee(
         emp_no        integer         primary key
        ,name          varchar2(20)    not null
);

insert into employee(emp_no, name)
             values (1,'Nancy');

insert into employee(emp_no, name)
             values (2,'Tom');

insert into employee(emp_no, name)
             values (3,'Jason');

insert into employee(emp_no, name)
             values (4,'Tom');



select count(distinct name) from employee;

COUNT(DISTINCTNAME)
-------------------
                  3
                  

drop table employee;








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