id type
---------------------
NULL ÆäËüÊÕÈë
NULL ÆäËüÊÕÈë
NULL ÆäËüÊÕÈë
NULL ÆäËüÊÕÈë
1 ÆäËüÊÕÈë
1 ÆäËüÊÕÈë
1 ÆäËüÊÕÈë
1 ÆäËüÊÕÈë
1 ÆäËüÊÕÈë
1 ÆäËüÊÕÈë
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where id <> 1 and id is null
NULL ²ÎÓëµÄÈκÎÔËËã½á¹û»¹ÊÇ NULL (³ýÁËISNULL£¬NULLIF)
nullÓë¿ÕÖµ ²»Ò»ÑùµÄ°É
SQL code:
--²éѯʱ£º
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--¸³ÖµÊ±:
×Ö¶ÎÃû=NULL
±È½Ïʱ Óà is Æ¥ÅäNULLÖµ
Èç¹û²»ÎªNULL ¾ÍÓÃÂß¼ÔËËã·ûÈ¥±È½Ï
ʹÓÃis null
»òÕßis not null
null = unknow
NULL Öµ¼ÆËãʱÓÐ3ÖÖ½á¹û
TRUE
FALSE
UNKNOWN
SQLÊÇÈýÖµÂß¼£¬YES NO ºÍ UNKOWN NULL=NULL ½á¹ûÊÇUNKOWN NULL=1 ½á¹ûÊÇUNKOWN
ÔÚWHERE£¬ ONÀïÃæÊÇÕâÑù¡£ÔÚGROUP BY ÀïÃæNULL=NULL ÊÇYES
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type Exception report
message
description The server encountered an internal error () that prevented it from fulfilling this request.
exception
org.apache.jas ......
sql 2005Êý¾Ý¿âÎÒÏëµÃµ½Ò»×Ö·û´®Îª:
sldkf|||sdeww
erkv|||rltdk
jemcl|||ligf
¾ÍÊÇ|||ºóÃæµÄ×Ö·ûÓÐʲôº¯ÊýÄܵõ½Âð£¿ÊÇÔÚsqlÓï¾äдµÄ£¬²»ÊÇÔÚÒ³ÃæÐ´µÄ£¬ÄÇλ¸ßÊÖÀ´Ö¸½ÌÏ£¬ÐÂÊÖ£¬Ð»Ð»
ÔÎ µ ......
clientserial devseral chunnelnum devdata5
CZ0001 308001 5000 11.1
CZ0001 308001 5001 11.2
CZ0001 308001 5002 11.3
CZ0001 3080 ......
CREATE PROCEDURE [selectvipcompany]
@username varchar(50),
@companyname varchar(50),
@endtime varchar(1)
AS
declare @sql varchar(1000)
set @sql=''
if (@username<>null and @username ......