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3.1 SQL

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An Introduction to Database System

3.2 SQL

[UNIQUE[]….]
[,CKECK ()]



(DEFAULT):
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Deptname CHAR(20) NOT NULL,


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CREATE TABLE Student
Sname CHAR(20) UNIQUE



Sname CHAR(20) NOT NULL,
Sclass CHAR(8)


CREATE TABLE SC(

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CREATE [UNIQUE] [CLUSTER] INDEX <> ON <>(<>[<>][,<>[<>] ]…)
<>
UNIQUE
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CREATE UNIQUE INDEX SCno ON SC(Sno ASCCno DESC)
An Introduction to Database System


Student(Sname)




 


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-
Course(CnoCnameCpnoCcredit)
SC(SnoCnoGrade)






FROM Student



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2.
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SELECT SnameSdeptSage
An Introduction to Database System

An Introduction to Database System

<>
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SELECT SnameSsex


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An Introduction to Database System

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[21]
SELECT SnoCno

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An Introduction to Database System

SELECT SnameSsex
An Introduction to Database System

SELECT SnameSdeptSage

An Introduction to Database System








------- --------- ---------- -------- -------
95006 db_desi%gn 19 CS
95002 a 19 IS
95004 19 IS
95005 18 IS
95003 21 MA
An Introduction to Database System


An Introduction to Database System






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