文档内容
- https://51jobs.taobao.com/ galerjim
1
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2 DB
3 DBMS
4 DBS
2 3
1
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3
3
4 ER
E-R —
5
1
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2 /
3
B hash
1
2 3 444
5 DBMS
1 /
( ) ( )
2 /
/
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1
2
3
6
1
2
1 3
1 ———
2
3
2
D m
:
DDD111 D2 Dn ( ) D1 D2 Dn
D1 D2 Dn ddd111 d2 dn dddiii i 1 2 n n
Tuple ddd111 d2 dn n n-tuple (Tuple)(
) ( )
Component d1 d2 dn di
Cardinal number Di i 1 2 n Di Di
mi i 1 2 n D1 D2 Dn M
A={a,b} B={1,2,0}
A B ={,,,,,}
B A = <0,a>,<0,b>,<1,a>,<1,b>,<2,a>,<2,b>
<0,a> a b 0 1 2 M=2*3=6
D1 D2 Dn
D1 D2 Dn n R D1 D2 Dn
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R n Degree
1 t
2 n=1 Unary relation n=2
Binary relation
3
4 (d1 d2 dn) (d2 d1 dn)
(d1 d2 di dj dn = d1 d2 dj di dn i
j = 1 2 n
Attribute n n
5
3
F R R F S K
F R
4 3
A R A
FFF RRR S K
R S R FF F
S
5
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1 R S n R S RRR SSS === {{{ ttt|||ttt t
2 R – S n R S R -SSS === {{{ ttt|||ttt t
3 R S n R S R SSS === {{{ ttt|||ttt t R S = R
(R-S
4 R: n k1 S: m kkk222 RRR×××SSS
5 R t R t[Ai]
R(A1 A2 … An) R tt RRR t R t[Ai]
t Ai
6 A t[A] A
A={Ai1 Ai2 Aik} AAAiii111 Ai2 AAAiiikkk A1 A2 AAAnnn A
t[A]=(t[Ai1] t[Ai2] ttt[[[AAAiiikkk]]]))) ttt A A {A1 A2
An} {Ai1 Ai2 AAAiiikkk}}}
7 tr ts
R n S mmm tr RRR tttsss S tr ts tr ts n + m n
R nnn m S mmm
8 Zx
RRR X Z XXX ZZZ ttt[[[XXX]]]===xxx x R Images Set Zx={t[Z]|t
t[X]=x}
R XXX x Z
9 RRReeessstttrrriiiccctttiiiooonnn : R
F(R) = {t|t R F(t)= ' '}
10 R A
R
11
R S = { | tr ts
A B R S
R S R S R A S B
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R S A B
R S= {tr ts| tr R ts S tr[A] = ts[B] }
R S B R S = {tr ts| tr ts tr[B] = ts[B] }
(Null)
R (LEFT OUTER JOIN LEFT JOIN)
S (RIGHT OUTER JOIN RIGHT
JOIN)
12 R (X Y) S (Y Z) X Y Z R Y S Y
R S P(X) P R
X
( ) X x Yx S Y
R÷S = {tr [X] | tr Y (S) YYYxxx x R x =tr[X]
SQL
1 SQL
1 2
3 4
5
2 SQL SQL
1 ( )
SQL(Oracle )
1
CREATE SCHEMA < > AUTHORIZATION < >[< >|<
>|< >]
CREATE SCHEMATEST AUTHORIZATION ZHANG
CREATE TABLETAB1(COL1 SMALLINT COL2 INT COL3 CHAR(20) COL4 NUMERIC(10 3)
COL5 DECIMAL(5 2))
ZHANG TEST TAB1
DROP SCHEMA < >
CASCADE( )
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RESTRICT( );
2
CREATE TABLE < >
< > < >[ < > ]
[ < > < >[ < >] ] …
[ < > ]
--
NOT NULL
UNIQUE
PRIMARY KEY:
DEFAULT < >:
Check < ( ) >: ,
NOT NULL
UNIQUE
PRIMARY KEY:
DEFAULT < >:
Check < ( ) >: ,
--
UNIQUE( )
PRIMARY KEY ( )
FOREIGN KEY ( ))) RRREEEFFFEEERRREEENNNCCCEEESSS <<< > [( )))]]]
Check(< >)
PRIMARY KEY UNIQUE
“ ” Student
CREATE TABLE Student
(((SSSnnnooo CCCHHHAAARRR(((999))) PPPRRRIIIMMMAAARRRYYY KKKEEEYYY //** **//
SSSSSnnnnnaaaaammmmmeeeee CCCCCHHHHHAAAAARRRRR(((((2222200000))))) UUUUUNNNNNIIIIIQQQQQUUUUUEEEEE //** SSnnaammee */
SSSssseeexxx CCCHHHAAARRR(((222))) SSSaaagggeee SSSMMMAAALLLLLLIIINNNTTT SSSdddeeepppttt CCCHHHAAARRR(((222000))))))
ALTER TABLE < >
[ ADD < > < > [ ] ]
[ DROP < > |< > ]
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[ ALTER COLUMN< > < > ]
Student “ ”
ALTER TABLE StudentADDS_entrance DATE
ALTER TABLE Student ALTER COLUMN Sage INT
ALTER TABLE Course ADD UNIQUE(Cname);
:( ) ALTER TABLE Student Drop Sage
DROP TABLE < > RESTRICT| CASCADE
RESTRICT ( )
CASCADE
Student DDRROOPP TTAABBLLEE SSttuuddeenntt CCAASSCCAADDEE ;;
3
DBA DBMS PRIMARY
KEY UNIQUE
CREATE [UNIQUE] [CLUSTER] INDEX < >
ON < > (< >[< >][,< >[< >] ]…)
< > ASC DESC ASC
UNIQUE
CLUSTER
CLUSTER
CREATE CLUSTER INDEX Stusname ON Student(Sname)
Student Sname Student Sname
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UNIQUE
- Student Course SC
CREATE UNIQUE INDEX SCno ON SC(Sno ASC Cno DESC)
UNIQUE UNIQUE DBMS
UNIQUE
DROP INDEX < >
Student Stusname DROP INDEX Stusname
2
Select A1 A2 An
From R1,R2,.., Rm
Where F
1
A(R) AAA=== AAA111 A2 AAAnnn
SELECT Sno SSSnnnaaammmeee
FROM Student
SSSEEELLLEEECCCTTT
< > *
SELECT Sno Sname Ssex Sdept , Sage
FROM Student
SELECT *
FROM Student
P.S:SELECT < >
SELECT Sname 2011-Sage /* 2011 */
FROM Student
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Sname 2011-Sage
1991
1992
SELECT Sname Year of Birth: ' 2004-Sage ISLOWER(Sdept)
FROM Student
Sname 'Year of Birth:' 2004-Sage ISLOWER(Sdept)
Year of Birth: 1984 cs
Year of Birth: 1985 is
SELECT Sname asNAME,'Year of Birth: ' as BIRTH
2011-Sage as BIRTHDAY,LOWER(Sdept) asDDDEEEPPPAAARRRTTTMMMEEENNNTTT
FROM Student;
NAME BIRTH BBBIIIRRRTTTHHHDDDAAAYYY DDDEEEPPPAAARRRTTTMMMEEENNNTTT
------- ---------------- ------------- ------------------------------------------------------
YYYeeeaaarrr ooofff BBBiiirrrttthhh::: 111999999111 cccsss
YYYeeeaaarrr ooofff BBBiiirrrttthhh::: 111999999222 iiisss
DISTINCT
SELECT DISTINCTSSSnnnooo FFRROOMM SSCC
DISTINCT
SSSEEELLLEEECCCTTT DDDIIISSSTTTIIINNNCCCTTT CCCnnnooo DDDDDIIIIISSSSSTTTTTIIIIINNNNNCCCCCTTTTT GGGGGrrrrraaaaadddddeeeee FFFFFRRRRROOOOOMMMMM SSSSSCCCCC;;;;;
SSSSSEEEEELLLLLEEEEECCCCCTTTTT DDDDDIIIIISSSSSTTTTTIIIIINNNNNCCCCCTTTTT CCCCCnnnnnooooo GGGrrraaadddeee FFFRRROOOMMM SSSCCC;;;
SELECT (ALL),
SSSSSEEEEELLLLLEEEEECCCCCTTTTT SSSSSnnnnnooooo FFFFFRRRRROOOOOMMMMM SSSSSCCCCC
SSSSSEEEEELLLLLEEEEECCCCCTTTTT AAAAALLLLLLLLLL SSSSSnnnnnooooo FFFFFRRRRROOOOOMMMMM SSSSSCCCCC
WHERE FFF
NOT +
SELECT Sname
FROM Student
WHERE Sdept= CS
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20
SELECT Sname Sage
FROM Student
WHERE Sage < 20 //NOT Sage>=20
: BETWEEN AND NOT BETWEEN … AND …
20~23 20 23
SELECT Sname Sdept Sage
FROM Student
WHERE Sage BETWEEN 20 AND 23 //Sage>=20 and Sage<=23
20~23
SELECT Sname Sdept Sage
FROM Student
WHERE Sage NOT BETWEEN 20 AND 23 //SSSaaagggeee<<<222000 ooorrr SSSaaagggeee>>>222333
IN < >, NOT IN < >
IS MA CS
SELECT Sname Ssex
FROM Student
WHERE Sdept IN ( 'IS' 'MA' 'CS' );
SELECT Sname Ssex
FROM Student
WHERE Sdept NOT IN ( 'IS' 'MA' '''CCCSSS''' )));;;
[NOT] LIKE < > [[[EEESSSCCCAAAPPPEEE < >>> ]
200215121
SELECT * SSEELLEECCTT **
FROM Student FFFRRROOOMMM SSStttuuudddeeennnttt
WWHHEERREE SSnnoo LLIIKKEE 222000000222111555111222111''' WWWHHHEEERRREEE SSSnnnooo === ''' 222000000222111555111222111 '''
% 000
_
% ___ % ___ \ ESCAPE < >
"DB_" 333 i
SELECT *
FROM Course
WHERE Cname LIKE 'DB\_%i_ _' ESCAPE ' \
ISNULL ISNOTNULL IS =
SELECT Sno Cno
FROM SC
WHERE Grade IS NOT NULL
AND OR AND OR
[NOT] IN
[NOT] BETWEEN … AND …
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IS MA CS
SELECT Sname Ssex
FROM Student
WHERE Sdept IN ( 'IS' 'MA' 'CS' )
SELECT Sname Ssex
FROM Student
WHERE Sdept= ' IS ' OR Sdept= ' MA' OR Sdept= ' CS '
ORDER BY
ASC DESC
ASC DESC
3
SELECT Sno Grade
FROM SC
WHERE Cno= ' 3 '
ORDER BY Grade DESC
COUNT [DISTINCT|ALL] *
COUNT [DISTINCT|ALL] < >
SUM [DISTINCT|ALL] < >>>
AVG [[[DDDIIISSSTTTIIINNNCCCTTT|||AAALLLLLL]]] <<< >
MAX [[[DDDIIISSSTTTIIINNNCCCTTT|||AAALLLLLL]]] <<< >
MIN [[[DDDIIISSSTTTIIINNNCCCTTT|||AAALLLLLL]]] <<< >
222000000222111555000111222
SELEEECCCTTT SSSUUUMMM(((CCCcccrrreeedddiiittt)))
FFFRRROOOMMM SSSCCC CCCooouuurrrssseee
WWWHHHEEERRRSSSSSnnnnnooooo====='''''222220000000000222221111155555000001111122222''''' AAAAANNNNNDDDDD SSSSSCCCCC.....CCCCCnnnnnooooo=====CCCCCooooouuuuurrrrrssssseeeee.....CCCCCnnnnnooooo;;;;;
CCCooouuunnnttt * , Where
GROUP BY
GROUP BY SSSEEELLLEEECCCTTT
having
3
SELECT Sno
FROM SC
GROUP BY Sno
HAVING COUNT(*) >3
3 90 90
SELECT Sno, COUNT(*)
FROM SC
Where Grade >90
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GROUP BY Sno
HAVING COUNT(*) >3
HAVING WHERE
WHERE
HAVING
3
1
INSERT
[INTO] < > [(< 1>[ < 2 > )]
VALUES (< 1> [ < 2>] )
1 1 2 2
INTO
NNNOOOTTT NNNUUULLLLLL
VALUES INTO
200215128 IIISSS 18
Student
INSERT
INTO Student (Sno Sname Ssex Sdept SSSaaagggeee)))
VALUES ('200215128' ' ' ' ' 'IS' 111888)))
Student
INSERT
INTO Student
VALUES ( 200215126 18 ''CCSS''));;
((( '''222000000222111555111222888''' '1 ')
INSERT
INTO SC(Sno CCCnnnooo)))
VALUES ( 222000000222111555111222888 1 )))
RDBMS GGGrrraaadddeee
IINNSSEERRTT
IIINNNTTTOOO SSSCCC
VALUES ( 222000000222111555111222888 1 NNNUUULLLLLL)))
SC GGGRRRAAADDDEEE
2
UPDATE < >
SET < >=< >>>[[[ <<< >=< >]
[WHERE < >]
SET < >
WHERE
WHERE
200215121 22
UPDATE Student
SET Sage=22
WHERE Sno=' 200215121 '
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1
UPDATE Student
SET Sage= Sage+1
UPDATE SC
SET Grade=0
WHERE 'CS'=
(SELETE Sdept
FROM Student
WHERE Student.Sno = SC.Sno)
3
DELETE
FROM < >
[WHERE < >]
WHERE
WHERE
200215128
DELETE
FROM Student
WHERE Sno= 200215128 '
DELETE
FROM SC
DDDEEELLLEEETTTEEE
FFFRRROOOMMM SSSCCC
WWWHHHEEERRREEE '''CCCSSS'''===
(((SSSEEELLLEEETTTEEE SSSdddeeepppttt
FFFRRROOOMMM SSStttuuudddeeennnttt
WWWWWHHHHHEEEEERRRRREEEEE SSSSStttttuuuuudddddeeeeennnnnttttt.....SSSSSnnnnnooooo=====SSSSSCCCCC.....SSSSSnnnnnooooo)))))
4
1
CREATE VIEW < > [(< > [ < >] )]
AS < >
[WITH CHECK OPTION]
ORDER BY DISTINCT
WITH CHECK OPTION UPDATE INSERT DELETE
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RDBMS CREATE VIEW SELECT
CREATE VIEW IS_Student
AS
SELECT Sno Sname Sage
FROM Student
WHERE Sdept= ‘IS’
WITH CHECK OPTION
CREATE VIEW IS_Student
AS
SELECT Sno Sname Sage
FROM Student
WHERE Sdept= 'IS'
WITH CHECK OPTION
WITH CHECK OPTION RRRDDDBBBMMMSSS IIISSS___SSStttuuudddeeennnttt Sdept=
'IS' SSSdddeeepppttt=== '''IIISSS''' SSSdddeeepppttt 'IS'
SSSdddeeepppttt Sdept ''IISS''
1
CCCRRREEEAAATTTEEE VVVIIIEEEWWW IIISSS___SSS111(((SSSnnnooo SSSnnnaaammmeee GGrraaddee))
AS
SSSEEELLLEEECCCTTT SSStttuuudddeeennnttt...SSSnnnooo SSSnnnaaammmeee Grade
FFFRRROOOMMM SSStttuuudddeeennnttt SC
WWWWWHHHHHEEEEERRRRREEEEE SSSSSdddddeeeeepppppttttt===== '''''IIIIISSSSS''''' AAAAANNNNNDDDDD
SSSSStttttuuuuudddddeeeeennnnnttttt.....SSSSSnnnnnooooo=====SSSSSCCCCC.....SSSSSnnnnnooooo AAAAANNNNNDDDDD
SC.Cno='1'
1 90
CCCRRREEEAAATTTEEE VVVIIIEEEWWW IIISSS___SSS222
AS
SELECT Sno Sname Grade
FROM IS_S1
WHERE Grade>=90
SELECT *
Student Student F_Student
DROP VIEW < >
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CASCADE
DROP VIEW
BT_S
DROP VIEW BT_S;
IS_S1
DROP VIEW IS_S1 CASCADE;
2 ,
SELECT
ViewResolution
20
SELECT Sno Sage
FROM IS_Student
WHERE Sage<20
SELECT Sno Sage
FROM Student
WHERE Sdept= 'IS' AND Sage<20
S_G 90
SELECT *
FROM S_G
WHERE Gavg>=90
S_G
CREATE VVVIIIEEEWWW SSS___GGG (((SSSnnnooo Gavg)
AS
SELECT Sno AAAVVVGGG(((GGGrrraaadddeee)))
FROM SC
GGGRRROOOUUUPPP BBBYYY SSSnnnooo
3
DBMS View Resolution
SQL2 R select select distinct
R WWWhhheeerrreee R Select
not null
INSERT DELETE UPDATA
SQL2 WITH CHECK OPTION DBMS
IS_Student 200215122
UPDATE IS_Student
SET Sname= ' '
WHERE Sno= ' 200215122 '
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UPDATE Student
SET Sname= ' '
WHERE Sno= ' 200215122 ' AND Sdept= 'IS'
IS_S 200215129 20
INSERT
INTO IS_Student
VALUES(‘95029’ ‘ ’ 20)
INSERT
INTO Student(Sno Sname Sage Sdept)
VALUES(‘200215129 ' ' ' 20 'IS' )
IS_Student 200215129
DELETE
FROM IS_Student
WHERE Sno= ' 200215129 '
DELETE
FROM Student
WHERE Sno= ' 200215129 ' AND Sdept= 'IS'
(1)
(2) IIINNNSSSEEERRRTTT UPDATE
DELETE
(3)
(4) GGGRRROOOUUUPPP BBBYYY
(5) DDDIIISSSTTTIIINNNCCCTTT
(6) FFFRRROOOMMM
(7)
4
1.
2.
3.
4.
5.
3 SQL
4
SQL
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1.
2.
3.
4.
5.
1
2
1
2
3
4 DDBBAA
5
3
MAC
4
GRANT REVOKE
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1 GRANT
GRANT
GRANT < >[,< >]...
ON < > < > [< > < >>]]
TO < >[,< >]...
[WITH GRANT OPTION];
GRANT DBA OOOwwwnnneeerrr
PPPUUUBBBLLLIIICCC
Student U1
GRANT SELECT
ON TABLE Student
TO U1;
Student U4
GGGRRRAAANNNTTT UUUPPPDDDAAATTTEEE(((SSSnnnooo))),,, SSSEEELLLEEECCCTTT
ON TABLE SSStttuuudddeeennnttt
TO U4;
2 RRREEEVVVOOOKKKEEE DBA REVOKE
REVOKE
REVOKE < >>>[[[,,,<<< >]...
ON < >>> <<< >>> >>>[[[,,,<<< > < >]
FROM < >[,< >>>]]]......... >>>[[[CCCAAASSSCCCAAADDDEEE|||RRREEESSSTTTRRRIIICCCTTT]]]
U4
REVOKE UPDATE(Sno)
ON TABLE Student
FROM U4;
SC
REVOKE SELECT
ON TABLESC
FROM PUBLIC;
U5 SC INSERT
REVOKE INSERT
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ON TABLE SC
FROM U5 CASCADE ; RESTRICT
U5 INSERT CASCADE U5 SC INSERT
U6 U6 U7 CASCADE U5
Grant Revoke
3 DBA
CREATE USER
CREATE USER
WITH DBA | RESOURCE | CONNECT
DBA
CONNECT , .
5
1
2 RDBMS
RDBMS 3
1
2
3
3 SQL
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4 RDBMS
RDBMS
4
5
Trigger (Event-Condition-Action
Rule) ECA
1
CREATE TRIGGER
CREATE TRIGGER < >
{BEFORE | AFTER} < INSERT UPDATE DDEELLEETTEE
> ON < >
FOR EACH {ROW | STATEMENT}
WHEN < >
< >
CREATE TRIGGER
:
1.
2.
3.
4. INSERT DDDEEELLLEEETTTEEE UUUPPPDDDAAATTTEEE
AAAFFFTTTEEERRR BBEEFFOORREE IINNSSTTEEAADD OOFF AFTER
5. FFFOOORRR EEEAAACCCHHH RRROOOWWW
FFFOOORRREEEAAACCCHHH SSSTTTAAATTTEEEMMMEEENNNTTT
6. (( ) WHEN
7. PL/SQL( Transact-SQL)
8 SSttoorreedd PPrroocceedduurree SQL
BEFORE Teacher 4000
4000 4000
CREATE TRIGGER Insert_Or_Update_Sal
BEFORE INSERT OR UPDATE ON Teacher
/* */
FOR EACH ROW /* */
AS BEGIN /* PL/SQL */
IF (new.Job=' ') AND (new.Sal < 4000) THEN
new.Sal :=4000;
END IF;
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END;
AFTER Teacher Sal_log
Sal_log
CREATE TABLE Sal_log
(Eno NUMERIC(4) references teacher(eno)
Sal NUMERIC(7 2)
Username char(10)
Date TIMESTAMP
)
2
1
BEFORE 2 SQL 3 AFTER
SQL UUUPPPDDDAAATTTEEE TTTeeeaaaccchhheeerrr SSSEEETTT SSSaaalll===888000000 WWWHHHEEERRREEE
Ename=' ';
Insert_Or_Update_Sal
SQL UUUPPPDDDAAATTTEEE TTTeeeaaaccchhheeerrr SSSEEETTT SSSaaalll===888000000 WWWHHHEEERRREEE EEEnnnaaammmeee===''' ';
Insert_Sal
Update_Sal
3 DROP TRIGGER < >>> OOONNN <<< >>>;;;
Teacher IIInnnssseeerrrttt___SSSaaalll
DDDRRROOOPPP TTTRRRIIIGGGGGGEEERRR IIInnnssseeerrrttt___SSSaaalll OOONNN TTTeeeaaaccchhheeerrr;;;
1 ?
2 ((( )
1 R(U) U X Y U R(U)
r r X Y X Y
Y X X Y
R(U) U
X Y U
X Y 1 1 1:1 X Y
Y X
X Y 1 n 1:n Y X
X Y m n m:n X Y
R(U) U X Y X Y Y X Y
X Y Y X Y
SC(Sno, Cno, Grade) (Sno, Cno) Grade
(Sno, Cno) Sno (Sno, Cno) Cno
X Y X Determinant
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2 R(U) X Y X X’ X’ Y,
Y X
3 X Y Y X Y X
(Sno,Cno) Grade (Sno,Cno) Sdept
Sno Sdept Sno Sno Cno
4 R(U) X Y (Y X) ,Y X Y Z Z Y Z X ,
: Y X X Y Z X
: Std(Sno, Sname Sdept, Mname)
Sno Sdept Sdept Mname
Mname Sno
5 K R K U KK R Candidate
Key
K
1 K
2.K R KKK
PPPrrriiimmmaaarrryyy KKKeeeyyy
Prime attribute
:
S(Sno,Sdept,Sage) Sno
SC Sno Cno Grade SSSnnnooo Cno
R P WWW AAA P W AAA
(P W AAA))) All-Key
6 R X R X X R
Foreign key
SC Sno Cno GGGrrraaadddeee Sno
Sno S Sno Sdept SSSaaagggeee Sno SC
3 1NF,2NF,3NF,BCNF
1 1NF R R 1NF
,
S-L-C(Sno, Sdept,Sloc, Cno,Grade) Sloc
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(Sno, Cno) F Grade
(Sno, Cno) P Sdept Sno
Sdept
(Sno, Cno) P Sloc
Sdept Sloc
S-L-C (Sno, Cno)
S-L-C
Sdept Sloc
(Sno, Cno)
-
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Sdept Sloc
S-L-C
SC Sno Cno Grade S-L Sno SSSdddeeepppttt Sloc
2 2NF R 1NF R 22NNFF
S-L-C(Sno, Sdept, Sloc, Cno, Grade) 11NNFF
S-L-CCC(((SSSnnnooo,,, SSSdddeeepppttt,,, SSSllloooccc,,, CCCnnnooo,,, GGGrrraaadddeee))) 2NF
SC Sno Cno Grade 22NNFF
S-L Sno Sdept SSSllloooccc 2NF
1NF 22NNFF 1NF
111NNNFFF 2NF
3 3NF RRR<<>> X YY Z Z , X Y
Y X Y Z R R 3NF R 3NF
3NF
SSS---LLL(((SSSnnnooo,,, SSSdddeeepppttt,,, SSSllloooccc))) 222NNNFFF SSS---LLL(((SSSnnnooo,,, SSSdddeeepppttt,,, SSSllloooccc))) 3NF
S-D(Sno Sdept) 333NNNFFF DDD---LLL(((SSSdddeeepppttt Sloc) 3NF
R 3NF RR 22NNFF
3NF 2NF
2NF
3NF
4 BC BCNF R 1NF X Y Y X
R R BCNF
R BCNF
R BCNF R 3NF R 3NF R
R BCNF R 3NF
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S Sno Sname Sdept Sage S Sno Sname
S 3NF S BCNF
SJP S J P s J P
S J P (J P S S J J P ,
SJP 3NF ( )
SJP BCNF,( )
1 P205
1
1
2
1
2
3
4
3
1
=
2
=
3
=
4
=
5
=
2
1
1
2
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3
4
3
4
5
6
2 E-R
E-R P213
3 EEE---RRR
P224
4
1 SQL
2
1
1
2
3
4
DBMS
DBMS
2
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3 P283
1
2.
3
1
2
4
P279
5
1 DBMS DBMS
1
2
3
4
2
UNDO REDO
1 REDO
UNDO
2 UNDO UNDO
UNDO
3 REDO REDO
REDO
3
1 DBA ,
2 DBA
3 DBA DBMS
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6 P287
1 T
2 D
1
/
2
1 1 2 222 1
1
2 1 2 111
3 1 222 1
1 2 2
3 P296
4
5 , P299
6 PP330011
7 PPP333000222
/ / offer
