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:




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(DDL)




(DDL) SQL, , , .

DDL :

CREATE TABLE

ALTER TABLE

DROP TABLE

CREATE INDEX

ALTER INDEX

DROP INDEX

(DML)

(DML) SQL, .

DML:

INSERT

UPDATE

DELETE

(DQL)

, (DQL) SQL.

SELECT

, , . .

.

(DCL)

SQL . DCL , , . DCL:

ALTER PASSWORD

GRANT

REVOKE

CREATE SYNONYM

. . :

START AUDIT

STOP AUDIT

He . , .

, .

COMMIT , .

ROLLBACK , .

SAVEPOINT , ROLLBACK.

SET TRANSACTION .

 

SQL.

SQL , .

 

SQL

CHAR() CHARACTER()
INTEGER INT
SMALLINT
NUMERIC(, ) DECIMAL(, ) DEC(, )
FLOAT ()
DATETIME ,

SQL , . , , , .

. , : 21 -375.18 62.3

, : 1.57 -3.149 2.5-6 0.78324

. : '' 'New York' ' . .'

(NULL). SQL .

SQL , SQL. , FindFirst, Recordset, SQL, WHERE.

Microsoft Jet Microsoft Visual Basic (VBA). Microsoft Jet ( Between, In Like) VBA. , VBA SQL 100 . , VBA SQL Microsoft Access, DAO OpenRecordset Microsoft Visual C++, Microsoft Visual Basic Microsoft Excel.

SQL- () . :

COUNT ;

SUM ;

AVG ;

MAX ;

MIN .

:

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: = (), > (), < (), >= ( ), <= ( ), <> ( );

: AND ( ""), OR ( ""), NOT ( );

:

IN , ;

BETWEEN , ;

LIKE . : % (), _ (), ;

IS NULL NULL-

 





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