SQL查詢語句Select
以下四句SQL查詢語句Select區別是什么?
1.sql2 = "select *from Info where BarCode ='" & BarCode.Text & "'and AnalysisID <>"" "
說明:
2.sql2 = "select *from Info where BarCode ='" & BarCode.Text & "'and AnalysisID <>'' "
說明:
3.sql2 = "select *from Info where BarCode ='" & BarCode.Text & "'and AnalysisID ="" "
說明:
4.sql2 = "select *from Info where BarCode ='" & BarCode.Text & "'and AnalysisID =‘’ "
說明:
引号要匹配。
2、4是匹配的。
一个是匹配 AnalysisID 空,一个是匹配不空。
还是插入源代码吧,CSDN爱加点东西
我的要求是:
1:BarCode ='" & BarCode.Text & "'
2:AnalysisID=空
需要用那句代碼呢?
源代碼為:
sql2 = "select *from Info where BarCode ='" & BarCode.Text & "' " '連接access
'
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