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SQL- :
SQL- CREATE INDEX;
SQL Server Enterprise Manager.
. , . . All Tasks / Manage Indexes Action . , , Databases Table, . Existing indexes .
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New - ;
Edit - ;
Delete - ;
Close - ;
Help - .
, New . Create New Index, (. . 3.30).
Index name ' , , , . . : Column - ' , Data type - , Length - , Nullable - NULL-, Precision - Scale - , .
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Index options :
Unique values - , . . , . NULL- . NULL- . ' , ;
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Clustered index - SQL- . , , ' . , , , , . , ;
Ignore duplicate values . Unique values . ' . ;
Do not recompute statistics (not recommended) - . ;
File group - , . ' / . , ;
Fill factor - . . SQL-. FILLFACTOR . FILLFACTOR. , , , FILLFACTOR , , 20. , 100 , ;
Pad index - Fill factor,
Drop existing - , , .
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DDL , , , , , . , DDL '.
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DDL SQL:
CREATE - , ' ;
DROP - , ' ;
ALTER - , ' .
DDL . , , , . , , , , .
DDL , SQL. , , , , . , , .
, , . , Microsoft SQL Server CREATE DATABASE, . ³, DROP DATABASE . ֳ , SQL.
', . , Microsoft SQL Server CREATE DATABASE :
CREATE DATABASE <NAME_DATABASE> ON <FILE1>, <FILE2>,...
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CREATE TABLE. , . , , , INSERT. CREATE TABLE - , . , .
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CREATE TABLE :
CREATE TABLE <TABLE NAME>
(<COLUMN NAME> <DATA TYPE> [(<SIZE>)],
<COLUMN NAME> <DATA TYPE> [(<SIZE>)]...);
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, , , , , , . , : . , ' SNUM STUDENTS USP, .
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SA.STUDENTS
, STUDENTS, (ID) SA.
, STUDENTS:
CREATE TABLE STUDENTS (SNUM INTEGER, SEAM CHAR (20), SIMA CHAR (10), SOTCH CHAR (15) STIP DECIMAL);
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ϳ , , . ALTER TABLE , . , . , :
ALTER TABLE <TABLE NAME> ADD <COLUMN NAME> <DATA TYPE> <SIZE>;
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, STUDENTS , :
ALTER TABLE STUDENTS ADD COURS INTEGER, SPEC CHAR (10);
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DROP TABLE <TABLE NAME>;
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, STUDENTS, , : DROP TABLE STUDENTS;
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