/* SQL Fundamentals
IN, NOT IN, NULL, NOT NULL
*/


/* List students who are in these teams: ITPROS, SYSDES or TECHSO.  */


select std_teamID, stdfname, stdlname
from students
where std_teamID = 'ITPROS' 
OR std_teamID = 'SYSDES' 
OR std_teamID = 'TECHSO';

select std_teamID, stdfname, stdlname
from students
where std_teamID IN ('ITPROS', 'SYSDES', 'TECHSO');


/* List students who are NOT in these teams:  ITPROS, SYSDES or TECHSO. */


select std_teamID, stdfname, stdlname
from students
where std_teamID NOT IN ('ITPROS', 'SYSDES', 'TECHSO');


/* List students who have not been assigned to a team.    */

select std_teamID, stdfname, stdlname
from students
where std_teamID IS NULL;


/* List students who are assigned to a team.    */

select std_teamID, stdfname, stdlname
from students
where std_teamID IS NOT NULL;

/* How many students are there? */

select count(*)
from students;


/* How many students have not been assigned to a team. */

select count(*)
from students
where std_teamID IS NULL;


/* How many students have been assigned to a team.  */

select count(*)
from students
where std_teamID IS NOT NULL;