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SQL
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: SQL (1 )
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3. .
/ :IBM PC, MS Access /OpenOffice dBase.
. :
- .
- Salespeople () :
., .
snum
sname
city
comm
- Customers () :
., .
cnum
cname
city
rating
- snum
- Orders () :
., .
- onum
amt
odate
cnum
snum
SQL . - SQL. , SQL , - - .
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- , . , , , , ( ), .
SELECT
, SELECT , . , :
SELECT snum, sname, ity, comm
FROM Salespeople;
1 SELECT
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SELECT | - . , . |
snum, sname | - . . , , , ; . |
FROM Salespeople | FROM - , SELECT, . . - (Salespeople). |
; | SQL . |
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, . (*) :
SELECT *
FROM Salespeople;
.