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µ±¸ø server sql Êý¾Ý¿âÌí¼ÓÒ»ÐÐʱ ÏëʹÐÐΪ null µÄÓòֵΪ 0
ÔÚ server sql Êý¾Ý¿âÉè¼Æ±íÀï ʹÓòµÄĬÈÏֵΪ (0) ͨ¹ýc#³ÌÐòÌí¼ÓÐÐʱÒÀÈ»ÊÇnull
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A ±í A±í
------------------------ ʵ¼ÊÏëÿÌí¼Ó1ÐÐ ½á¹ûΪ ------------------------------------
Ãû³Æ ÊýÁ¿1 ÊýÁ¿2 Ãû³Æ ÊýÁ¿1 ÊýÁ¿2
ÓñÃ× 10 null ÓñÃ× 10 0
СÂó null 20 СÂó 0 20
Ò²¾ÍÊÇnull ÔÚÌí¼ÓʱΪ0
Çë½Ì
not null default 0
isnull(Öµ,0)
SQL code:
if object_id('[A]') is not null drop table [A]
go
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1,Name1....test1,1,99
1,Name1....test1,3,99
1,Name2....test2,1,101
1,Name2....test2,3,101
1,Name3....test3,2,101
1,Name1....test1,4,101
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1,Na ......