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nvl( ) º¯Êý
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NVL(eExpression1, eExpression2)
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eExpression1, eExpression2
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select nvl(a.name,'¿ÕµÃ') as name from student a join school b on a.ID=b.ID
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isNaN º¯Êý
isNaN(expression:Object) : Boolean
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function checknum()
{
if ( isNaN (frm.num.value))
{
alert("ÇëÊäÈëÊý×Ö");
frm.num.focus();
}
lpad º¯Êý
ÔÚ Oracle /PLSQLÖÐ, lpad º¯Êý½«×ó±ßµÄ×Ö·û´®Ìî³äÒ»Ð©ÌØ¶¨µÄ×Ö·û,
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lpad ( string1, padded_length, [ pad_string ] )
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A £º SQL> select lpad ('test',8,0) from dual;
LPAD ('TEST',8,0)
----------------
0000test
B£º select lpad ('test',8) from dual;
LPAD ('TEST',8)
 
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create table emp2_log(
uname varchar2(20),
action varchar(10),
atime date
);
create or replace trigger trig
after insert or delete or update on emp2 for each row //°óÔÚÒ»ÕűíÉÏ,before after ¶¼¿É
ÒÔ,beforeÊÇ ²åÊý¾Ý֮ǰ£¬afterÊÇÖ®ºó
begin
&nb ......
ÔÚPL/SQLÖÐʹÓÃÕóÁд¦ÀíÊÇÒ»¸öºÜºÃµÄ×ö·¨(È磬ʹÓÃbulk collectºÍforall)¡£ÅúÁ¿´¦ÀíÄܹ»´ó´ó¼õÉÙPL/SQLÓï¾äÖ´ÐÐÒýÇæµÄ»·¾³Çл»´ÎÊý£¬´Ó¶øÌá¸ßÆäÐÔÄÜ¡£
¡¡¡¡ÁíÒ»¸öÓÅÐãʾÀýÊǰѴ洢¹ý³ÌÖеÄËùÓдúÂë·ÅÈëËø¶¨µÄÈí¼þ°üÖУ¬ÕâÑù¿ÉÒÔÉú³ÉÄ£¿éµ¥Ôª¡£°Ñ´æ´¢¹ý³Ì·ÅÈëÈí¼þ°üÀï¿ÉÒÔʵÏÖÏà¹Ø³ÌÐòºÍ¹¦ÄܵķÖ×é¡£µ±
µ¥¸ö°ü±»Ê¹Óà ......
When queried, virtual columns appear to be normal table columns, but
their values are derived rather than being stored on disc. The syntax
for defining a virtual column is listed below.
column_name [datatype] [GENERATED ALWAYS] AS (expression) [VIRTUAL]
If the datatype is omitted, it is determin ......
(1)SEQNAME.NEXTVALÀïÃæµÄÖµÈçºÎ¶Á³öÀ´£¿¿ÉÒÔÖ±½ÓÔÚinsert into test values(SEQNAME.NEXTVAL) ÊÇ¿ÉÒÔÓà ÕâÑù£º
SELECT tmp#_seq.NEXTVAL
INTO id_temp
from DUAL; È»ºó¿ÉÒ ......
package com.chinacache.boss.queryservice.service.impl;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import com.chinacache.boss.queryservice.excepti ......