在查询总和表达式中缺少运算符vb网

Question

Dim da As OleDbDataAdapter = New OleDbDataAdapter("Select sum[Shark Individual Weight] from FishCaught'", myConnection) 
Dim ds As DataTable = New DataTable() 
da.Fill(ds) 
DataGridView1.DataSource = ds 

myConnection.Close() 

你好。我正在使用vb.net连接到ms访问。我不断收到错误'查询表达式中缺少运算符'。我想知道我的sql语句有什么问题。

Dim da As OleDbDataAdapter = New OleDbDataAdapter("Select Sum([Shark Individual Weight]) From FishCaught Where ([OperationID]) = '" & TextBoxOpID4.Text & "'", myConnection) 
    Dim ds As DataTable = New DataTable() 
    da.Fill(ds) 
    DataGridView2.DataSource = ds 

我想我的SQL语法是错误的。应该怎么写呢？我得到这个错误'标准表达式中的数据类型不匹配'。如果我只是写'Dim da As OleDbDataAdapter = New OleDbDataAdapter（“Select Sum（[Shark Individual Weight]）from FishCaught'，总和将会显示，所以我认为在WHERE子句中有错误，任何帮助将不胜感激，谢谢。

Answer 1

这是你的代码

Dim da As OleDbDataAdapter = New OleDbDataAdapter("Select sum[Shark Individual Weight] from FishCaught'", myConnection) 
Dim ds As DataTable = New DataTable() 
da.Fill(ds) 
DataGridView1.DataSource = ds 

myConnection.Close() 

应该是代码必须是这样的

Dim da As OleDbDataAdapter = New OleDbDataAdapter("Select sum(The_Name_Of_The_Field) from FishCaught'", myConnection) 
Dim ds As DataTable = New DataTable() 
da.Fill(ds) 
DataGridView1.DataSource = ds 

myConnection.Close() 

是这样的，试试这个FINAL

Dim da As OleDbDataAdapter = New OleDbDataAdapter("Select sum(Shark__Individual_Weight) as FishWeight from FishCaught'", myConnection) 
    Dim ds As DataTable = New DataTable() 
    da.Fill(ds) 
    DataGridView1.DataSource = ds 

    myConnection.Close() 

尝试改变Shark Individual Weight到Shark_Individual_Weight它会工作

Answer 2

总和是一个函数，你有一个令人不安的单引号，即：

"Select Sum([Shark Individual Weight]) From FishCaught" 

Answer 3

"Select Sum([field name]) From FishCaught"应该工作。你是否检查过数据库中的字段名称，它不应该包含任何空格。为了使字段名称更具可读性，您可以用“_”替换任何空格。