Question

School uniform is available at M/s Sheetal Private Limited. They have maintained SCHOOL_UNIFORM Database with two relations viz. UNIFORM and COST. The following figure shows the database schema and its state.

School Uniform Database
Attributes and Constraints				Table: COST
Table: UNIFORM				UCode	Size	COST Price
Attribute	UCode	UName	UColor	1	M	500
Constraints	Primary Key	Not Nul	-	1	L	580
Table: COST				1	XL	620
Attribute	UCode	Size	Price	2	M	810
Constraints	Composite Primary Key		>0	2	L	890
Table: UNIFORM				2	XL	940
UCode	UName	UColor		3	M	770
1	Shirt	White		3	L	830
2	Pant	Grey		3	XL	910
3	Skirt	Grey		4	S	150
4	Tie	Blue		4	L	170
5	Socks	Blue		5	S	180
6	Belt	Blue		5	L	210
				6	M	110
				6	L	140
				6	XL	160

1. Can they insert the following tuples to the UNIFORM Relation? Give reasons in support of your answer.
   i) 7, Handkerchief, NULL
   ii) 4, Ribbon, Red
   iii) 8, NULL, White
2. Can they insert the following tuples to the COST Relation? Give reasons in support of your answer.
   i) 7, S, 0
   ii) 9, XL, 100

Answer 1

1. i) Yes, it can be inserted.
   ii) Yes, It can be inserted.
   iii) No. It cannot be inserted as UName cannot be NULL.
2. i) No, it cannot be inserted as the price must be > 0.
   ii) Yes, it can be inserted.