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Dim cmd1 As New SQLCommand

cmd1.C

cmd1.CommandText ="(S elect [FPrintNo] from {SHProcRptMain} where [FBillNo]=(S elect [FSourceBillNo] from {vwICBill_2} where FBatchNo = '" & dr("批号") & "'))"

Dim T1 As New QueryBuilder

T1.TableName = "T1"

T1.S electString = cmd1.CommandText

T1.Build

'Dim cmd2 As New SQLCommand

'cmd2.C

'cmd2.CommandText ="(S elect 数据 from 电容出厂 where 客户料号=tbl.Current("客户对应物料代码") And 打印标记=cmd1)"

老师，2个数据库的内容如何连起来查询？另子查询查出来的结果是数组不唯一，如何处理最后得出惟一值？

S elect 数据 from 电容出厂 where 客户料号=tbl.Current("客户对应物料代码") And 打印标记=(S elect [FPrintNo] from {SHProcRptMain} where [FBillNo]=(S elect [FSourceBillNo] from {vwICBill_2} where FBatchNo = '" & dr("批号") & "'))

[此贴子已经被作者于2017/9/23 17:55:45编辑过]

Dim g0 As String

Dim g1 As String

Dim cmd1 As New SQLCommand

cmd1.C

cmd1.CommandText ="(S elect top 5000 [FPrintNo] as [随工单号] from {SHProcRptMain})"

g0 = cmd1.ExecuteScalar()

g1 = Mid(g0,1,Instr(g0,"$")-1)+Right(g0,4)

MessageBox.Show(g1)

请教一下，上述代码，为何会有报错：参数“Length”必须大于或等于 0。？

2楼的问题解决了，应该是有空值。筛掉了就可以了。谢谢！

Dim g0 As String

Dim g1 As String

Dim cmd1 As New SQLCommand

cmd1.C

cmd1.CommandText ="(S elect top 5000 [FPrintNo] as [随工单号] from {SHProcRptMain} where [FPrintNo]<>' ')"

g0 = cmd1.ExecuteScalar()

g1 = Mid(g0,1,Instr(g0,"$")-1)+Right(g0,4)

MessageBox.Show(g1)

老师您好，
多数据源查询统计，我们如下这样做了，但是有报错，烦请您帮忙看看问题可能出在哪里？

Dim dt1 As DataTable

Dim cmd1 As New SQLCommand

cmd1.C

cmd1.CommandText ="S elect top 5000 [FPrintNo] as [随工单号],[FBillNo] as [FCR号] from {SHProcRptMain} where [FPrintNo]<>' ' group by [FPrintNo],[FBillNo]"

dt1 = cmd1.ExecuteReader

Dim dt2 As DataTable

Dim cmd2 As New SQLCommand

cmd2.C

cmd2.CommandText ="S elect top 5000 [FBatchNo] as [产品批号],[FSourceBillNo] as [FCR号] from {vwICBill_2} where [FSourceBillNo]<>' ' group by [FBatchNo],[FSourceBillNo]"

dt2 = cmd2.ExecuteReader

Dim dt3 As DataTable

Dim cmd3 As New SQLCommand

cmd3.C

cmd3.CommandText ="S elect [客户料号],[打印标记] as [随工单号],[数据] from {电容出厂} where [打印标记]<>' ' group by [客户料号],[打印标记],[数据]"

dt3 = cmd3.ExecuteReader

Dim dt4 As DataTable

Dim cmd4 As New SQLCommand

cmd4.C

cmd4.CommandText ="S elect [客户料号],[批号],[实发数量] from {销售出库单}"

dt4 = cmd4.ExecuteReader

Dim hbsql As String ="s elect a.*,(s elect b.[数据] from {dt3} b where a.[客户料号]=b.[客户料号]) as [测试数据],(s elect [打印标记] c.from {dt3} c where a.[客户料号]=c.[客户料号]) as [随工单号],(s elect d.[FSourceBillNo] from {dt2} d where a.[批号]=d.[FBatchNo]) as [产品批号],(S elect e.[购货单位],e.[客户料号],e.[批号],e.[实发数量] from {dt4} e group by [客户料号],[批号]) a"

Dim q As new QueryBuilder

q.TableName = "查询表1"

q.SelectString = hbsql

q.Build

此主题相关图片如下：1.bmp

老师，单个字段表格里字符串长度不够怎么办？一直弹窗，是否能解决最大长度的问题？

Dim sql3 As String ="S elect Top 10 * From {电容出厂}"

Dim cmd3 As New SQLCommand

cmd3.C

Dim dt3 As DataTable

Dim cmb3 As WinForm.ComboBox

cmd3.CommandText = sql3

dt3 = cmd3.ExecuteReader()

Dim f3 As New Filler

f3.SourceTable = dt3

f3.DataTable = DataTables("电容出厂")

f3.Fill()

SQL数据库	A	B	C
	1	2	3

DBA数据库	B	C	D
	2	3	4

FOX整合数据库	A	B	C	D
外部数据表(SQL)	1	2	3	4

老师，如上，如何根据B,C 2个相同字段，将2个不同数据库的表的相关内容整合到FOX的外部数据表SQL表里？

S ELECT TOP 100 ibe.FBatchNo,i.FBillNo,t3.FFlowCardNo,ib.FBillNo,t4.FCardSort

FROM ICStockBill AS ib INNER JOIN ICStockBillEntry AS ibe ON ib.FInterID=ibe.FInterID

INNER JOIN ICMO AS i ON i.FInterID=ibe.FICMOInterID

INNER join ICShop_FlowCard t3 ON t3.FSourceBillNo=i.FBillNo

inner join (s elect distinct FCardSort,FID from Item999) as t4 on t4.FID=t3.FID

老师，如上这么一长串，Dim sql As String =“如上”

因为窗口小，连成一行容易眼花，能否像上面这样在SQL里分行来写进DIM里面？

主题：多数据库数据查询