我有一个带有15个参数的dbo.individuals sql表。该表应从后面绑定到gridview，但是在绑定之前，应根据另一个表dbo.activities的计算参数更新6个参数，该表包含10个参数。每个人都没有记录的活动，也没有数量不定的活动。查询2中使用的参数是varchar（50）数据类型。
我尝试了两种方法： 1：要在一个查询中加入两个表，但是用这种方法，我未能成功建立设想的个人表。 2：我尝试加载带有查询1的个人数据集，使用读取器循环浏览这些数据，并使用查询2中的varchar（50）id加载由另一个读取器循环浏览并经过分析的活动的数据集该表已建立。最终表应混合使用查询1和查询2的参数。但是，我无法管理查询2的功能。
Private Sub BindData()
' define table
Dim dta As New DataTable()
dta.Columns.AddRange(New DataColumn() {
New DataColumn("RecordID", GetType(Integer)),
New DataColumn("tagID", GetType(String)),
New DataColumn("animalID", GetType(String)),
New DataColumn("calvingdate", GetType(String)),
New DataColumn("24hoursallowancesup1", GetType(String)),
New DataColumn("24hoursallowancesup2", GetType(String)),
New DataColumn("accumulatedallowancesup1", GetType(Integer)),
New DataColumn("accumulatedallowancesup2", GetType(Integer)),
New DataColumn("visitswithin24hours1", GetType(Integer)),
New DataColumn("visitswithin24hours2", GetType(Integer)),
New DataColumn("totalvisits1", GetType(Integer)),
New DataColumn("totalvisits2", GetType(Integer))
})
Dim konr As String = " "
Try
Dim PrimaryConnection As String = ConfigurationManager.ConnectionStrings("PrimaryConnection").ToString()
Dim sqlhk As String = "Select * FROM Individuals ORDER BY Individuals.tagID ASC"
Dim cnhk As New SqlConnection(PrimaryConnection),
cmdhk As New SqlCommand(sqlhk, cnhk)
cnhk.Open()
Dim readerhk As SqlDataReader = cmdhk.ExecuteReader
While readerhk.Read()
konr = readerhk("tagID")
'define and reset for each loop
Dim acc1 As Integer = 0
Dim acc2 As Integer = 0
Dim accperiod As String = 0
Dim accumulatedsup1 As Integer = 0
Dim accumulatedsup2 As Integer = 0
Dim cowactive1 As String = "Y"
Dim cowactive2 As String = "Y"
Dim dayvisits1 As Integer = 0
Dim dayvisits2 As Integer = 0
Dim totalvisits1 As Integer = 0
Dim totalvisits2 As Integer = 0
Dim eatensup1day As Integer = 0
Dim eatensup2day As Integer = 0
Dim eatentotal1 As Integer = 0
Dim eatentotal2 As Integer = 0
Try
Dim caConnection As String = ConfigurationManager.ConnectionStrings("PrimaryConnection").ToString()
Dim sqlca As String = "Select Activities.[ID], Activities.[VisitTime], Activities.[GramSup1], Activities.[GramSup2], Activities.[Comment] FROM Activities WHERE Activities.[EarTag] = '" & konr & "' ORDER BY Activities.[EarTag] ASC"
Dim cnca As New SqlConnection(caConnection),
cmdca As New SqlCommand(sqlca, cnca)
'cmdca.Parameters.AddWithValue("@konr", readerhk("tagID"))
cnca.Open()
Dim readerca As SqlDataReader = cmdca.ExecuteReader
While readerca.Read()
Dim vti As DateTime = DateTime.Parse(readerca("VisitTime"))
Dim fsk As TimeSpan = Now() - vti
Dim def As Integer = fsk.TotalHours
'would logically not become negative, but for certainty, we ensure the figure is positive
If def < 0 Then
def = -def
Else
def = def
End If
'visits last 24h
If def <= 24 And (readerca("GramSup1") + readerca("GramSup2")) > 0 Then
dayvisits1 += 1
dayvisits2 += 1
eatensup1day += readerca("GramSup1")
eatensup2day += readerca("GramSup2")
End If
'visits in accumulationperiod
If def <= (24 * Session("accperiod")) And (readerca("GramSup1") + readerca("GramSup2")) > 0 Then
totalvisits1 += 1
totalvisits2 += 1
eatentotal1 += readerca("GramSup1")
eatentotal2 += readerca("GramSup2")
End If
End While
Dim vtik As DateTime = DateTime.Parse(readerhk("calvingdate"))
Dim fskk As TimeSpan = Now() - vtik
Dim defk As Integer = fskk.TotalHours
If defk < 0 Then
defk = -defk
Else
defk = defk
End If
If defk >= (Session("accperiod") * 24) Then
accperiod = (Session("accperiod") * 24)
Else
accperiod = defk
End If
Dim start1 As DateTime = vtik.AddDays(Session("startday1"))
Dim end1 As DateTime = vtik.AddDays(Session("endday1"))
Dim start2 As DateTime = vtik.AddDays(Session("startday2"))
Dim end2 As DateTime = vtik.AddDays(Session("endday2"))
If DateTime.Parse(Now()) >= DateTime.Parse(start1) And DateTime.Parse(Now()) <= DateTime.Parse(end1) Then
accumulatedsup1 = accperiod / 24 * readerhk("24hoursallowancesup1") - eatentotal1
Else
cowactive1 = "N"
End If
If DateTime.Parse(Now()) >= DateTime.Parse(start2) And DateTime.Parse(Now()) <= DateTime.Parse(end2) Then
accumulatedsup2 = accperiod / 24 * readerhk("24hoursallowancesup2") - eatentotal2
Else
cowactive2 = "N"
End If
dta.Rows.Add(readerhk("Id"), readerhk("tagID"), readerhk("animalID"), readerhk("calvingdate"), readerhk("24hoursallowancesup1"), readerhk("24hoursallowancesup2"), If(cowactive1 = "N", Nothing, accumulatedsup1), If(cowactive2 = "N", Nothing, accumulatedsup2), If(cowactive1 = "N", Nothing, dayvisits1), If(cowactive2 = "N", Nothing, dayvisits2), eatentotal1, If(cowactive2 = "N", Nothing, totalvisits2))
readerca.Close()
readerca = Nothing
cnca.Close()
cnca = Nothing
Catch ex As Exception
Response.Write("Cow log data error: " & ex.Message)
End Try
End While
Catch ex As Exception
Response.Write("Cow listing error:" & ex.Message)
End Try
'-- Declaring of a DataView to be used as DataSource for a second grid
Dim dv As New DataView(dta) With {
.Sort = "visitswithin24hours1 ASC, visitswithin24hours2 ASC"
}
' BIND DATABASE WITH THE GRIDVIEW
GridView1.DataSource = dv
GridView1.DataBind()
End Sub
我想要一个表，将个人的ID列为第1列，这是来自个人表/查询1的四个参数，以及来自活动表/查询2的六个参数。 我对此很业余，问题是应该从活动表/查询2计算的六个参数全为零（默认值），并且查询2显然未激活。我希望有人能帮助我。
表1 /个人的示例数据和数据类型：
表2 /活动的示例数据和数据类型：
答案 0 :(得分：1)
我认为您要查找的是对两个表进行“交叉应用”：
类似的东西
Select *
FROM Individuals I CROSS APPLY
(
Select min([VisitTime]) as first_visit, count(*) as Activities_cnt
FROM Activities
WHERE Activities.[EarTag] = I.tagID
) as Activities_cum
ORDER BY Individuals.tagID ASC;