Count(*) - count(column_Name) : COUNT « Aggregate Functions « Oracle PL / SQL






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

Count(*) - count(column_Name)

   
SQL>
SQL> create table product(
  2          product_id              integer
  3          ,price                  number(7,2)
  4          ,description            varchar2(75)
  5          ,onhand                 number(5,0)
  6          ,reorder                number(5,0)
  7          ,supplier_no            integer
  8  );

Table created.

SQL> insert into product(product_id, price, description, onhand, reorder)values (1,2.50,'Oracle',100,20);

1 row created.

SQL> insert into product(product_id, price, description, onhand, reorder)values (2,23.00,'SQL Server',null,null);

1 row created.

SQL> insert into product(product_id, price, description, onhand, reorder)values (3,null,'MySQL',null,null);

1 row created.

SQL> insert into product(product_id, price, description, onhand, reorder)values (4,1.50,'DB2',50,10);

1 row created.

SQL> insert into product(product_id, price, description, onhand, reorder)values (5,10.50,'Java',100,20);

1 row created.

SQL> insert into product(product_id, price, description, onhand, reorder)values (6,45.00,'C++',null,null);

1 row created.

SQL> insert into product(product_id, price, description, onhand, reorder)values (7,19.99,'Javascript',3,5);

1 row created.

SQL> insert into product(product_id, price, description, onhand, reorder)values (null,4.50,'Ruby',null,null);

1 row created.

SQL>
SQL> select count(*) - count(product_id) from product;
COUNT(*)-COUNT(PRODUCT_ID)
--------------------------
                         1

1 row selected.

SQL>
SQL> drop table product;

Table dropped.

SQL> --








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