SQL Class Exercise: Table Update
              
Objective: Apply insert, update and delete operations to modify the employee 
table. Table specifications and data are linked to the course web page.           
0. Use the show create table schema.table_name command to list the structure
   of the employee table.

   
1. Select yourSchema.employee to project all data in key order.


2. By default MySQL runs in autocommit mode. Issue a START TRANSACTION command
   before a series of update commands that may be committed or rolled back.  
   ROLLBACK will "undo" commands given in the transaction. COMMIT will make 
   the work final and complete the transaction.

   
3. Inserting Data:
   a. Enter a row for empno 8000, ename 'Brown', job 'Analyst', manager 
      (NULL), hiredate '2013-06-10', salary (DEFAULT).


   b. Store another row including only values for primary key (8001), foreign
      key(use some manager's empno for this value), and for any columns having
      a NOT NULL constraint.
        
        
   c. Prepare a single insert statement for entering values for two employees:
      empno ename  job       manager  hiredate    salary 
      8002  Gray   NULL      7566     2013-06-11  3900.00
      8003  Green  manager   7839     2013-06-11  4400.00 
      
     
4. Modifying Data:
   a. For Employee 8001, set job to 'MANAGER' and the manager column value to 
      7839 (do this with a single UPDATE statement).

      
   b. For any employees having a NULL value in salary, set salary to 1.00.


   c. Increase the salary for all managers by 10%.

   
5. Deleting Data:
   a.  Delete Employee 7369 from the Employee table.

  
   b.  Delete all Employees hired during the year 2013.

   
6. Query your updated table projecting all columns with rows ordered by key.


7. Issue a rollback, then query again to show the table has been restored.


_____________________________________________________________________________
Table     Column        dataType     Constraint
Employee  empno         int(4)       primary key
          ename         char(10)     not null and unique
          job           varchar(9)   default null
          manager       decimal(4)   (recursive) foreign key
          hireDate      date         default null*
          salary        decimal(7,2) default 1.00