, NOT - . , NULL , NOT, :
SELECT *
FROM Customers
WHERE city IS NOT NULL;
city.
NULL( ), .
SELECT *
FROM Customers
WHERE NOT city IS NULL;
- .
NOT IN:
SELECT *
FROM Salespeople
WHERE city NOT IN ('London', 'San Jose');
-
SELECT *
FROM Salespeople
WHERE NOT city IN ('London', 'San Jose');
21.
NOT BETWEEN NOT LIKE.
21 NOT IN
.
1. ( , , ) Orders.
2. = 1001.
3. : , , , .
4. SELECT , San Jose .
5. .
6. 1000.
7. .10.
8. =< 100, .
9. ?
SELECT *
FROM Orders
WHERE (amt < 1000 OR NOT (odate = #03.10.1990# AND cnum > 2003));
10. ?
SELECT *
FROM Orders
WHERE NOT ((odate = #03.10.1990# OR snum > 1006) AND amt > = 1500);
11. ?
SELECT snum, sname, city, comm
FROM Salespeople
WHERE (comm > +.12 OR comm <.14);
12. 3 4 1990.
13. Peel Motika.
14. , A G.
15. C.
16. NULL amt().
- SELECT FROM?
- ?
- ?
- ?
- ? .
- ?
- IN?
- BETWEEN?
- LIKE?
- * ??
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2.
3.
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COUNT
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SUM
.
AVG
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SELECT , , . SUM AVG.
COUNT, MAX, MIN, . , MIN , MAX .
SUM , , 1:
SELECT SUM (amt)
FROM Orders;
1
(Expr1000). , _, :
SELECT Sum([amt]) AS _
FROM Orders;
, , , :
SELECT Sum([amt]) AS [ ]
FROM Orders;
2
- ( 2):
SELECT AVG (amt)
FROM Orders;
3