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SQL




SQL FoxPro 5.0

FoxPro, , , (), . , SQL ( , ).

 

, SQL FoxPro, : "" FoxPro, SQL , ; SQL , FoxPro.

 

" ", - , . FoxPro SQL, , FoxPro, . , (, - ) SQL *

 

, , SQL FoxPro " " - , "-", FoxPro , SQL.

 

SQL FoxPro , , . - ; () SQL.

 

FoxPro " SQL", SPT (SQL-pass-through) , - SQL, SQL, "" . , , SQL FoxPro.

 

SQL.

 

, " SQL, - :

 

)

 

1 _ 2

 

- = (), <>,!=, # () >, >=,<,<=, , , == ( ) [NOT] LIKE ( ),

 

, , "" , () , = FoxPro (. ANSI EXACT).

 

 

[NOT] LIKE

 

- , () % _. [NOT] LIKE , % - _.

 

) , , AND, OR NOT

 

) " " - , , ( )

 

1 [NOT] BETWEEN 2 AND 3

-

[NOT] (2 £1 AND 1£3)

 

[NOT] IN (_)

-

[NOT] (=1 OR £2 OR =N)

 

 

) ,

 

_ _ ALL ( SELECT)

 

, , SELECT - , - , , . , .

 

_ _ ANY | SOME ( SELECT)

 

, , SELECT - , , . , .

 

[NOT] EXISTS (_SELECT)

 

, () , .. () .

 

_ [NOT] IN (_SELECT)

 

, IN, , , , ; , ( ) .

 

 

 

CREATE TABLE __ [NAME* - 128 - _] [FREE*]

[( 1 [ 1)],

[( 2] [ 2])],

..

[( n] [ n])],

[ ]

 

( FREE - - , ; , , , CREATE TABLE)

 

 

-

_

_

[(_ [, ( - ])]

 

FoxPro , , () ().

 

C n - Character - c n

D - - Date -

T - - dateTime - -

N n d Numeric - n, d

F n d Floating numeric - n, d

,

I - - Integer -

B - d douBle -

Y - - currencY -

L - - Logical -

M - - Memo -

G - - General -

 

. , SQL.

 

-

 

[NULL | NOT NULL] - ( ) NULL; , (SET-) NULL; , NULL (UNIQUE) ;

 

[CHECK l [ERROR* ]] - , "" ;

 

 

[DEFAULT ]

 

[PRIMARY KEY | UNIQUE] - () | ; , :

 

[REFERENCES __ [TAG () ]] - [ ]

 

-

 

[PRIMARY KEY TAG* () |, UNIQUE TAG* ] - ( ) | ; ();

 

[, FOREIGN KEY TAG* _

REFERENCES _ [TAG* ]] - () ,

 

[, CHECK [ERROR* ]]) - , "" ;

 

 

 

DROP TABLE _ | _ |? [RECYCLE]

; ? ; RECYCLE , "" Windows c , .

 

 

DROP VIEW _

 

 

ALTER TABLE _

ADD | ALTER [COLUMN] _

_ [(_ [, ])]

[NULL | NOT NULL]

[CHECK __

[ERROR ____]]

[DEFAULT __]

[PRIMARY KEY | UNIQUE]

[REFERENCES __

[TAG ()_]]

 

 

ALTER TABLE _

ALTER [COLUMN] _

[NULL | NOT NULL]

[SET DEFAULT __]

[SET CHECK __

[ERROR ____]]

[DROP DEFAULT]

[DROP CHECK]

 

ALTER TABLE _

[DROP [COLUMN] _]

[SET CHECK __

[ERROR ____]]

[DROP CHECK]

[ADD PRIMARY KEY __

TAG ()___]

[DROP PRIMARY KEY]

[ADD UNIQUE [TAG _]]

[DROP UNIQUE TAG _]

[ADD FOREIGN KEY [__]

TAG _

REFERENCES __

[TAG __]]

[DROP FOREIGN KEY TAG _]

[RENAME COLUMN __ TO __]

 

, ALTER TABLE CREATE TABLE ALTER - , ADD - , DROP - , SET - , RENAME - .

 

. , FoxPro SQL Create Index (, Drop Index). , , - FoxPro , Index (.).

 

 

.

 

INSERT INTO _ [(__])]

VALUES (_)

 

_ - dbf- ( - ) ; ;

, , , , ; , , , . , (. DEFAULT CREATE TABLE), - NULL ( SET- NULL ON)

 

.

1) FoxPro - INSERT INTO _ ( SELECT), , - SCAN (. )

2) , FoxPro , - - ., APPEND, INSERT FoxPro.

 

 

 

UPDATE [__!]_

SET _=

[WHERE _]

 

; WHERE, , .

 

 

 

DELETE FROM [__!]_

[WHERE _]

 

[, ,] .

 

. , , .. - FoxPro PACK; RECALL. , SET- DELETED.

 

 





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