count(distinct state) : COUNT « Aggregate Functions « Oracle PL / SQL






count(distinct state)

  

SQL>
SQL> create table emp(
  2           emp_id                integer         primary key
  3          ,lastname               varchar2(20)    not null
  4          ,firstname              varchar2(15)    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));

Table created.

SQL>
SQL>
SQL> insert into emp(emp_id,lastname,firstname,midinit,street,city,state,zip,shortZipCode,area_code,phone,company_name)values
  2                      (1,'Jones','Joe','J','1 Ave','New York','NY','11202','1111','212', '221-4333','Big Company');

1 row created.

SQL> insert into emp(emp_id,lastname,firstname,midinit,street,city,state,zip,shortZipCode,area_code,phone,company_name)values
  2                      (2,'Smith','Sue','J','1 Street','New York','NY','11444','1111','212', '436-6773','Little Company');

1 row created.

SQL> insert into emp(emp_id,lastname,firstname,midinit,street,city,state,zip,shortZipCode,area_code,phone,company_name)values
  2                      (3,'X','Peggy','J','1 Drive','New York','NY','45502','2222','212', '234-4444','Medium Company');

1 row created.

SQL> insert into emp(emp_id,lastname,firstname,midinit,street,city,state,zip,shortZipCode,area_code,phone,company_name)values
  2                      (4,'Murdy','Jill', null,'930 Eady St','New York','NY','45452','6458','212', '634-7733','Wilton Company');

1 row created.

SQL> insert into emp(emp_id,lastname,firstname,midinit,street,city,state,zip,shortZipCode,area_code,phone,company_name)values
  2                      (5,'Oper','Carl','L','19 Studio Drive','New York','NY','67672','3234','212', '243-4243','Wesson and Smith Company');

1 row created.

SQL>
SQL> select count(distinct state) from emp;

COUNT(DISTINCTSTATE)
--------------------
                   1

1 row selected.

SQL> drop table emp;

Table dropped.

   
    
  








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