oracle decodeʹÓ÷½·¨
Êý¾Ý¿âÖо³£ÓÃ0,1 À´±êʶij×ֶΣ¬×÷Ϊ¿ª·¢ÈËÔ±¿ÉÄÜÖªµÀËüµÄÒâÒ壬µ«ÎÒÃÇÈÃËüÏÔʾÔÚGridÁбíÉϱØÐëÏÔʾËüµÄʵ¼Êº¬Ò壬һ°ãÎÒÃÇ¿ÉÒÔÔÚ´úÂëÖжÁÊý¾ÝԴʱ¿ÉÒÔ×÷´¦Àí£¬Í¬Ê±ORACLEÖÐÓÃdecodeÒ²ÊDz»´í·½·¨¡£
decode(Ìõ¼þ,Öµ1,·ÒëÖµ1,Öµ2,·ÒëÖµ2,...Öµn,·ÒëÖµn,ȱʡֵ)
¸Ãº¯ÊýµÄº¬ÒåÈçÏ£º
IF Ìõ¼þ=Öµ1 THEN
¡¡¡¡¡¡¡¡RETURN(·ÒëÖµ1)
ELSIF Ìõ¼þ=Öµ2 THEN
¡¡¡¡¡¡¡¡RETURN(·ÒëÖµ2)
¡¡¡¡¡¡¡¡......
ELSIF Ìõ¼þ=Öµn THEN
¡¡¡¡¡¡¡¡RETURN(·ÒëÖµn)
ELSE
¡¡¡¡¡¡¡¡RETURN(ȱʡֵ)
END IF
Àý:decode(CONTROLLER.Energy_Saving,0,'·ñ','ÊÇ') as IsSaving
½âÊÍÈçÏÂ:ÅжÏCONTROLLER.Energy_Saving×Ö¶Î,Èç¹ûΪ0,¾ÍÈÃ×Ö¶ÎÏÔʾΪ"·ñ"£¬Èç¹û²»Îª0£¬¾ÍÈÃËüÏÔʾΪ“ÊÇ”¡£
Ïà¹ØÎĵµ£º
ËäȻѧϰJavaºÜ¾ÃÁË£¬×Ô¼ºÒ²Á¬½Ó¹ýһЩÊý¾Ý¿â£¬±ÈÈçmysqlÖ®ÀàµÄ£¬Èç½ñÄØ£¬Ò²Ñ§Ï°ÁËÒ»¶Îʱ¼äµÄOracle£¬È»¶øÄØ£¬½ñÌìÊÇÎÒµÚÒ»´ÎÁ¬½ÓOracle£¬ºÙºÙ£¬Ó¦¸Ã»¹²»ËãÌ«³Ù°É¡£
½ñÌìÄØ£¬Óе㱿׾£¬´ó¼ÒĪЦ£¡
ÎÒÕâÊÇÒ»¸ö²éѯÀý×Ó
Ê×ÏÈ£¬Ô ......
¹ØÓÚµ¼³ö
¡¡¡¡ÔÀí
¡¡¡¡Í¨¹ýsqlplusµÄµÄ±¨±í¹¦ÄÜÉú³ÉÎı¾Îļþ£¬µ«²úÉúµÄÎı¾ÎļþÒò·ÖÎöÔÒò´æÔÚ¿ÕÐÐÏÖÏó£¨Ö»ÓлسµÃ»ÓÐÆäËü£©£¬¿ÉÒÔͨ¹ýµÚÈý·½·½Ê½´¦ÀíÒ»ÏÂÉú³É±ê×¼Îı¾
¡¡¡¡A ѧϰ¹ý³Ì
¡¡¡¡1¡¡½¨±í
¡¡¡¡
¡¡¡¡SQL>CREATE TABLE TESTINOUT(ID NUMBER(10), USERNAME VARCHAR2(10), DATE1 DATE, MONEY NUMBER(6 ......
¹ØÓÚOracle 10g ¹éµµ·½Ê½µÄÌÖÂÛ£º¹Ø±Õ¹éµµ/ÆôÓÃÉÁ»Ø»Ö¸´Çø¹éµµ(Oracle 10gÐÂÌØÐÔ)/ÆôÓÃÀàOracle9iµÄ¹éµµ
×¢£ºÔÚOracle°²×°¹ý³ÌÖУ¬Èç¹ûÊý¾Ý¿âÊÇ×Ô¶¯´´½¨µÄ£¬ÄÇô¸ÃÊý¾Ý¿â×î³õµÄ´æµµÄ£Ê½ÊÇÓɲÙ×÷ϵͳָ¶¨µÄ¡£Í¨³£Çé¿öÏ£¬¹éµµÈÕÖ¾ÔÚOracleÊý¾Ý¿â°²×°½áÊøºóÐèÒªÊÖ¹¤´´½¨¡£
»·¾³£ºOracle 10g 10.2.0.1.0/Windows 2003 ......
SQLÖеĵ¥¼Ç¼º¯Êý
1.ASCII
·µ»ØÓëÖ¸¶¨µÄ×Ö·û¶ÔÓ¦µÄÊ®½øÖÆÊý;
SQL> select ascii(A) A,ascii(a) a,ascii(0) zero,ascii( ) space from dual;
A A ZERO SPACE
--------- --------- --------- ---------
65 97 48 32
2.CHR
¸ø³öÕûÊý,·µ»Ø¶ÔÓ¦µÄ×Ö·û;
SQL> select chr(54740) zhao,chr(65) chr65 from d ......