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SQL. . , , SQL .

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Structured Query Language. 5

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SQL- 5NT. 25

 

 


 

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. 1.

 

(. 1). : . . , , , . , , . , , . .

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, , . , . Oracle, Microsoft, Sybase, Informix, IBM, Borland.

 

 

Structured Query Language

 

SQL

 

SQL (Structured Query Language) . SQL , 70- IBM Research. IBM System R. - .

SQL 1989 . ( SQL/89 SQL1). SQL1 ANSI/ISO, . , , SQL.

1992 . SQL, SQL/92 SQL2. , , SQL/89. , SQL2.

1999 , SQL3. SQL1 SQL2 , SQL3 . SQL3 "- SQL" - . , . .

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SQL-

 

SQL- SQL, . , , , . . (. 2). SQL , , . ANSI SQL92.

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. 2. SQL-

 

 

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. 3. SQL

 

 

 

 

. () SQL , . SQL92 128 . -. DB2, , 8 , . , (, , , ), , . , . .

, , , , , diasoft. , , - , , dbo.tResource dbo dbo.

, . , , . , , .

, , . , , , . , , { ), . , BRIEF ( ) tRESOURCE ( ) : tRESOURCE.BRIEF.

, , . , BIRTH_DATE BIRTHDAYS, SAM, : SAM.BIRTHDAYS.BIRTH_DATE

 

SQL

 

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. , . ( UNICODE), .

 

SQL92 :

CHARACTER(n) CHAR(n) n . n , n , .

NUMERIC[(n,m)], DECIMAL[(n,m)] DEC[(n,m)] , n , m .

 

INTEGER INT .

 

SMALLINT .

, SQL1 , INT SMALLINT ( ), , . INTEGER , , a SMALLINT , . .

 

FLOAT[(n)] , . n , . .

 

REAL , , , FLOAT.

 

DOUBLE PRECISION , REAL.

 

VARCHAR(n) .

NCHAR(n) .

NCHAR VARYING(n) . I

I(n) .

BIT VARYING(n) .

DATE .

TIMESTAMP() .

INTERVAL .

 

, . , , . MEMO . -, ORACLE LONG, DB2 - LONG VARCHAR, SYBASE MS SQL Server TEXT.

, . DATE TIMESTAMP -, .

. .

. :

 

314 -612.716 + 551.702

 

, SQL , .

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2.9-4 -134.2357 0.5426718

 

, 2,9 -4, 0,00029.

 

:

 

' ..' '-'

 

, . , :

'I can''t' I can't.

, MS SQL Server Informix, :

 

"" "New York"

 

, , . SQL2 (, ) . .

, . . , :

 

mm/dd/yyyy 5/19/2006 hh:mm am/pm 2:18 PM

dd.mm.yyyy 19.5.2006 hh.mm.ss 14.18.08

yyyy-mm-dd 2006-5-19 hh:mm:ss 14:18:08

ISO yyyy-mm-dd 2006-5-19 hh.mm.ss 14.18.08

 

TIMESTAMP yyyy-mm-dd-hhmm.ss.nnnnnn

TIMESTAMP 2006-05-19-14.18.08.048632

 

SQL2 , ISO, , , . . , , , ORACLE. MS SQL Server:

 

March 15, 2006 15 2006 3/15/2006 3-15-06 2006 MAR 15

 

:

15:30:25 3:30:25 3:30:25 3

 

ORACLE 15-MAR-06

 

SQL , (+), (-), (*) (/). (/) , , .

, SQL , , . , CURRENT_DATE, , . SQL, . SQL2 , CURRENT_DATE, CURREN_TIME, CURREN_TIMESTAMP, USER, SESSION_USER SYSTEM_USER.

5NT() :

DSIDENTIFIER numeric(15,0) 0. ;

DSCOMMENT varchar(255);

DSACC_SWIFT char(35);

DSVARFULLNAME40 varchar(40) ..

 

 


SELECT

 

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SELECT , SELECT. , , , .

FROM , , .

WHERE , . , , .

GROUP BY . . , , , .

HAVING , , GROUP BY. , WHERE, .

ORDER BY () . , . , ( SELECT ). .

 

 

 

 


. 4. SELECT

 

SELECT .

 

select ( , ):

 

Select < >

From < >

 

:

 

1. (tInstitution).

 

Select *

From tInstitution

 

* , .

 

2. , (tInstitution).

 

Select Name

From tInstitution

 

 

3. , (tInstitution), .

SELECT DISTINCT ( ) ALL ( ). , . , , SELECT. ALL . , .

 

Select DISTINCT Name

From tInstitution

 

3. , (tInstitution). .

 

Select Name, Address3, Phone1

From tInstitution

 

4. , , , (tInstitution). , . as .

 

 

Select Name as Klient, Address3 as Address, Phone1 as Phone

From tInstitution

 

WHERE

 

. . . select :

 

Select < >

From < >

Where < >

 

:

 

= (),

<> ( ),

< (),

<= ( ),

> (),

>= ( )

 

, .

tOperPart . . 5.

 

 

tOperPart

OperationID DSIDENTIFIER
ResorceID DSIDENTIFIER (tResource)
OperSetID DSIDENTIFIER (tOperSet)
OperTypeID DSIDENTIFIER (tPropertyUsr)
BalanceID DSIDENTIFIER (tResource)
  OperDate DSOPERDAY
  QtyBs DSBIGMONEY ,

:

 

1. 06.06.2006.

Select *

From tOperPart

Where OperDate = '20060606'

 

2. , 5000 .

Select *

From tOperPart

Where QtyBs <= 5000

 

3. "".

Select *

From tInstitution

Where Name = ' ""'

 

. - . / / . SQL : AND, OR, NOT:

 

AND ( A AND B) , . , .

 

4. 06.06.2006 1000 .

Select *

From tOperPart

Where OperDate = '20060606'

and QtyBs <= 1000

 

OR ( A OR B) , . , .

 

5. 06.06.2006 1000 .

Select *

From tOperPart

Where OperDate = '20060606'

or QtyBs <= 1000

 

 

NOT ( NOT A) . , .

 

6. , 5000 .

Select *

From tOperPart

Where NOT QtyBs <= 5000

 

:

 

. IN (), , .

 

<> in (<>)

 

7. 06.06.2006, 08.06.2006, 09.06.2006.

Select *

From tOperPart

Where OperDate IN ('20060606', '20060608', '20060609')

 

Where OperDate = '20060606' or OperDate = '20060608' or OperDate = '20060609'

 

NOT IN ( ).

 

BETWEEN () ... AND... ( ... ...) .

 

<> between <> and <>

 

8. , 5000 . 10000 .

Select *

From tOperPart

Where QtyBs BETWEEN 5000 AND 10000

 

- Where QtyBs >= 5000 and QtyBs <= 10000

 

NOT BETWEEN ( ).

 

, , LIKE ( ).

<> LIKE < > , , < >. :

 

  • _ () ;
  • % () ;
  • .

 

9. , .

Select *

From tInstitution

Where Name like ' "%'

 

(NULL-)

 

- , NULL-. , . , , NULL-, 0, 0. . (, , NULL- ). NULL

 

<> IS NULL <> IS NOT NULL

 

, ,

 

<> = NULL <> <> NULL

 

, SQL92, , . SQL92 - NULL- - NULL-, ( , , , , SELECT DISTINCT NULL-.) , NULL.

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