PL/SQL ѧϰ±Ê¼Ç3
SQL> var a number
SQL> begin
2 :a :=1000;
3 end;
4 /
PL/SQL procedure successfully completed.
SQL> edit
Wrote file afiedt.buf
1 begin
2 dbms_output.put_line(:a);
3* end;
SQL> /
ͨ¹ýÕâ¸ö´úÂë¿ÉÒÔ¿´³öͨ¹ýpl/sql³õʼ»¯¸³ÖµµÄBind variable¿ÉÒÔ±»ÆäËûPl/sql³ÌÐòµ÷ÓÃ
%type ÀàÐÍÓ¦Óõϰ Èç¹ûÇ°ÃæÓõÄÊÇdatabase columnµÄ»° ÄÇô²»¿ÉÒÔ¼Ónot null,Ç°ÃæÒýÓõÄÊÇÉùÃ÷µÄ±äÁ¿¿ÉÒÔÓ¦ÓÃnot null
A NOT NULLdatabase column constraint does not apply to variables that are declared using %TYPE.
Therefore, if you declare a variable using the %TYPEattribute that uses a database column defined as NOT
NULL, you can assign the NULLvalue to the variable.
eg:
°ó¶¨±äÁ¿
A bind variable is a variable that you declare in a host environment.
Bind variables can be used to pass run-time values, either number or character, into or out of one or more PL/SQL programs. The PL/SQL
programs use bind variables as they would use any other variable. You can reference variables declared in the
host or calling environment in PL/SQL statements, unless the statement is in a procedure, function, or
package. This includes host language variables declared in precompiler programs, screen fields in Oracle Developer Forms applications, and iSQL*Plus bind variables.
°ó¶¨±äÁ¿¿ÉÒÔÔÚÖ÷»ú»·¾³ÏÂÉùÃ÷ ¿ÉÒÔÔÚsqlplus ÕâÖÖÓ¦ÓóÌÐòÏÂÉùÃ÷ È»ºópl/sql³ÌÐòÀ´µ÷Óà µ÷ÓÃÐèÒªÔڸñäÁ¿Ç°¼Ócolon
¸³ÖµµÄʱºò¿ÉÒÔʹÓà exec :var_name := 10000; or begin :var_name := 1000 end; »òÕßÊÇÔÚPL/SQLÖи³Öµ
print(sqlplus command)¿ÉÒÔ´òÓ¡³öÕâ¸öÖµ
SQL> var result number
SQL> begin
2 select (sal*12) + nvl(comm,0)
3 into :result
4 from emp
5 where empno = 7369;
6 end;
7 /
PL/SQL procedure successfully completed.
SQL> print result
RESULT
------
9600
SQL> exec :result = 10000
BEGIN :result = 10000; END;
*
ERROR at line 1:
ORA-06550: line 1, column 15:
PLS
Ïà¹ØÎĵµ£º
ÔÚÊý¾Ý¿âÓ¦ÓóÌÐò·¢²¼Ê±£¬¿Í»§¶Ë°²×°ÔÚ¾ÖÓòÍøÖеÄÖ÷»úAÉÏ£¬sql server °²×°ÔڸþÖÓòÍøµÄÖ÷»úBÉÏ¡£¿Í»§¶ËÈí¼þÖаüº¬ÓÐËüÒªÁ¬½ÓµÄÊý¾Ý¿âµÄÐÅÏ¢¡£ÈçÊý¾ÝÔ´£¬·þÎñÆ÷Ãû³Æ£¬Êý¾Ý¿âµÈ£¬ÊµÀý£ºdata source=SQLOLEDB;SERVER=DongZi\sqlExpress;uid=sa;pwd=123;database=MachineRoom
¡£ÄÇôÎÒÃÇÔÚÖ÷» ......
ÔÚ.Net Framework 3.5 ÖУ¬×¶¯ÈËÐĵľÍÊÇÔö¼ÓÁËLINQ¹¦ÄÜ£¬LINQÔÚÊý¾Ý¼¯³ÉµÄ»ù´¡ÉÏÌṩÁËеÄÇáÐÍ·½Ê½¡£ÓÐÁËLINQ£¬ÎÒÃÇ´´½¨µÄ²éѯÏÖÔھͱà³ÌÁË.Net ¿ò¼ÜµÄÒ»¸ö³ÉÔ±£¬ÔÚ¶ÔÒª²Ù×÷µÄÊý¾Ý´æ´¢Ö´Ðвéѯʱ£¬»áºÜ¿ì·¢ÏÖËûÃÇÏÖÔڵIJÙ×÷·½Ê½ÀàËÆÓÚϵͳÖеÄÀàÐÍ¡£Õâ˵Ã÷£¬ÏÖÔÚ¿ÉÒÔʹÓÃÈÎÒâ¼æÈÝ.Net µÄÓïÑÔÀ´²éѯµ×²ãµÄÊý¾Ý´æ´¢£¬Õ ......
ÔÚGoogleÉÏʹÓÓsql ·ÖÒ³”¹Ø¼ü×Ö½øÐÐËÑË÷£¬¼¸ºõËùÓеĴ𰸶¼ÊÇÄÇÈýÌõ¡£Æä¶þЧÂÊ×î¸ß£¬ÆäÈýʹÓÃÓα꣬ЧÂÊ×î²î¡£
ÏÂÃæÊÇÄÇÈýÖÖ·½·¨ £¨²åÈë´úÂëûÓÐsqlÑ¡Ï
·½·¨1£º
ÊÊÓÃÓÚ SQL Server 2000/2005
SELECT TOP Ò³´óС *
from table1
WHERE ......
1¡¢ÔÚÁíһ̨»úÆ÷ÉϽ¨Á¢¶ÀÁ¢µÄÊý¾Ý¿â·þÎñÆ÷£¬×÷ΪÁ´½ÓÄ¿±ê
2¡¢±¾µØÊý¾Ý¿â·þÎñÆ÷ÉÏÌí¼Ó“Á´½Ó·þÎñÆ÷”£º
Ãû×Ö£ºËæ±ãȡһ¸öÃû×Ö
·þÎñÆ÷ÀàÐÍ£ºÑ¡ÔñÊý¾ÝÔ´£ºMicrosoft OLE DB Provider for SQL Server
Êý¾ÝÔ´£ºÐ´±ðÃû£¨ÔÚ¿Í»§¶ËÍøÂçʵÓù¤¾ßÖÐÉèÖã©
Ñ¡ÖÐRPCºÍRPCÊä³ö ......
SQL code¶¯Ì¬sqlÓï¾ä»ù±¾Óï·¨
1 :ÆÕͨSQLÓï¾ä¿ÉÒÔÓÃExecÖ´ÐÐ
eg: Select * from tableName
Exec('select * from tableName')
Exec sp_executesql N 'select * from tableName'
-- Çë×¢Òâ×Ö·û´®Ç°Ò»¶¨Òª¼ÓN
2:×Ö¶ÎÃû£¬±íÃû£¬Êý¾Ý¿âÃûÖ®Àà×÷Ϊ±äÁ¿Ê±£¬±ØÐëÓö¯Ì¬SQL
eg: declare @fname varchar(20)
......