IBM USA (USA) hh.mm AM/PM 9.04 PM
, . , , (CURDATE CURTIME) . USER (), .
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, , TIMESTAMP, .
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FORMAT
7, , SQL, . SQL , , FORMAT SQL, , . FORMAT :
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, , , , SUM ( COMPUTE).
FORMAT , , , . FORMAT , FORMAT . FORMAT:
FORMAT NULL '_ _ _ _ _ _ _';
FORMAT BTITLE 'Orders Grouped by Salesperson';
FORMAT EXCLUDE (2, 3);
NULL _ _ _ _ _ _ _ ; 'Orders Grouped by Salesperson' ; . , , ORDER BY, . FORMAT , .
, . SET FORMAT; , , . , FORMAT COLUMN :
COLUMN odate FORMAT dd-mon-yy;
10-Oct-90 , .
COMPUTE, , :
SELECT odate, amt
FROM Orders
WHERE snum = 1001
COMPUTE SUM (amt);
Peel, , .
, COMPUTE . ,
BREAK ON odate;
, odate . :
COMPUTE SUM OF amt ON odate;
ON BREAK.
SQL ANSI, , comm * 100. , , , .
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| ABX(X) | X ( ) |
| CEIL(X) | X , . |
| FLOOR (X) | X , . |
| GREATEST(X,Y) | . |
| LEAST(X,Y) | . |
| MOD(X,Y) | X Y. |
| POWER(X,Y) | X Y. |
| ROUND(X,Y) | X Y. Y , . |
| SING(X) | X < 0, X > 0. |
| SQRT(X) | X. |
, , , .
| LEFT(<string>,X) | () X . |
| RICHT(<string>,X) | X |
| ASCII(<string>) | ASCII . |
| CHR(<ASCIIcode>) | ASCII. |
| VALUE(<string>) | . CHAR VARCHAR, . VALUE('3') 3 INTEGER. |
| UPPER(<string>) | . |
| LOWER(<string>) | . |
| INlTCAP(<string>) | . PROPER. |
| LENGTH(<string>) | . |
| <string>||<string> | , . ( || ). |
| LPAD(<string>,X,'*') | '*', , , X. |
| RPAD(<string>,X, ") | LPAD, , . |
| SUBSTR(<string>,X,Y) | Y X. |
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| DAY(<date>) | . MONTH (), YEAR (), HOUR (), SECOND () . |
| WEEKDAY(<date>) | . |
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| NVL(<column>,<value>) | NVL (NULL TO VALUE) <value> NULL , <column>. <column> =NULL, NVL . |
INTERSECT MINUS
UNION, 14, , . INTERSECT () MINUS (). INTERSECT , , MINUS , , . ,
SELECT *
FROM Salespeople
WHERE city = 'London'
INTERSECT
SELECT *
FROM Salespeople
WHERE 'London' IN (SELECT city
FROM Customers
WHERE Customers.snum = Salespeople.snum);
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, , , , , , . ,
SELECT *
FROM Salespeople
WHERE city = 'London'
MINUS
SELECT *
FROM Salespeople
WHERE 'London' IN (SELECT city
FROM Customers
WHERE Customers.snum = Salespeople.snum);
, , , , . MINUS DIFFERENCE ().
