ISO SQL:2003 :
,
SELECT
ROW_NUMBER()
. ROW_NUMBER() OVER . , :
SELECT * FROM (SELECT ROW_NUMBER() OVER (ORDER BY key ASC) AS rownumber, columns FROM tablename) AS foo WHERE rownumber <= 10ROW_NUMBER : key , , key . key , .
RANK()
RANK() OVER , ROW_NUMBER, n . , top-10 :
SELECT * FROM (SELECT RANK() OVER (ORDER BY age ASC) AS ranking, person_id, person_name, age FROM person) AS foo WHERE ranking <= 1010 . , , 11 .
54. . CISC, RISC VLIW :
. ́ (, , , ), ( ). 1970- , - 4- . , , . 8- 16- 1970- .
CISC. CISC , . , (, ). , .
CISC- : ;
, ; ; ;
; -.
- i8086/8088 - , , , , . , , , . . CISC-, . , - - - - .
, , , . RISC-, (Reduced Instruction Set Computer).
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RISC. RISC (Reduced Instruction Set Computers) () , CISC (Complex Instruction Set Computer)- . . . . RISC - . (, ) ; , . RISC - , , CISC - . RISC - 2 - 4 CISC - , , (30 %). 4 RISC: 1. , .
2. .
3. - ( , ; \). 4.
VLIW. CISC RISC VLIW. VLIW , . , , VLIW Multiflow, . , , VLIW, AP-120B/FPS-164/FPS-264 Floating Point Systems, 80- - . , , [5]. FPS-64 64 , .
VLIW , , . , , . , , RISC- , VLIW . , . EPIC , RISC- .
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55. () ():
, .
. , ( ), . . 13.3.
, -, ( ) ( - , ).
. . 13.4, ; Tz ; ; ' (. 13.6J.
. 13.3.
. 13.4.
iCp | Ts, | V | , |
\ ^-"^ | 20%- | arain | |
=,/0 | =0,7/(*) | -=,9/(:0) | |
/= 1/(4,5^2) | Kv=\iajK0Tz) | /=1/(1,7^0) | |
=0,8 + + 0,5 | Kv=0,7Tz!(Kot:) =+0, | =ë/( =+0,35 | |
= =0,95/(:) =2,4; =0,4 | =2,0; =0,4 | =1,47</(0) =1,3; =0,5 |
, (). . 13.21 , -, 1...3 , 2 . .
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10 20 30 40
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. 13.21 , , , . , , . . .