show incorrect/correct example for each cmd/query

---------------
Queries
---------------

Selection:

correct: select ( age == 12 ) people ;
incorrect: select ( age ))))) people ;

Projection:

correct: project ( age ) people ;
incorrect: x

Renaming:

correct: rename ( age, years old ) ;
incorrect: x

Set Union:

correct: x
incorrect: x

Set Difference:

correct: x
incorrect: x

Cross Product:

correct: x
incorrect: x

-------------------
Commands
-------------------

Open:

correct: OPEN people ;
incorrect: OPEN ;

Close:

correct: CLOSE people ;
incorrect: CLOSE ;

Save:

correct: SAVE people ;
incorrect: SAVE ;

Exit:

correct: EXIT ;
incorrect: EXIT people ;

Show:

correct: SHOW people ;
incorrect: SHOW ;

Create:

correct: CREATE TABLE people ( age INTEGER, name VARCHAR ( 20 ) ) PRIMARY KEY ( name ) ;
incorrect: CREATE TABLE people age name ;

Update:

correct: x
incorrect: x

Insert:

correct: INSERT INTO people VALUES FROM ( 12, "Benny" ) ;
incorrect: INSERT INTO people 12 "Benny" ;

Delete:

correct: x
incorrect: x