我正在尝试使用以下代码使用ADO net连接Access 2007"accdb"文件,但我收到错误Unrecognized Database format,可能的原因是什么?
OleDbConnection conn = new
OleDbConnection("PROVIDER=Microsoft.Jet.OLEDB.4.0;
Data Source=C:/MyWorkers.accdb");
try
{
conn.Open();
MessageBox.Show("Connected");
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
Run Code Online (Sandbox Code Playgroud) 我一直收到同样的错误:缺少操作员.我已经查看过这段代码三次但找不到它.有敏锐眼光的人可以帮忙吗?
WHERE ([Letter Status].[Letter_Status] = “Agreed” AND [Research].[Site] = 9)
OR ([Telephone Status].[Details]= “Agreed” AND [Research].[Site] = 9)
Run Code Online (Sandbox Code Playgroud) 当我的C#(.NET 3.5)应用程序尝试访问MS Access 2007数据库时,该OleDbReader.GetString()方法抛出异常:
指定演员表无效.
我究竟做错了什么?
OleDbCommand cmd = null;
OleDbDataReader reader = null;
String queryString = "SELECT ids.ENUM_H, bas.[BAS BACnet Object Type/Instance] FROM [OV2 BAS] AS bas INNER JOIN [OV2 RefID] AS ids ON bas.[Ref ID] = ids.[Ref ID]";
this.Open();
try
{
cmd = new OleDbCommand(queryString, this._conn);
reader = cmd.ExecuteReader();
if (!reader.HasRows)
{
Exception e = new Exception("Read of mapping table returned no results.");
throw e;
}
else
{
while (reader.Read())
{
Int32 index;
String classTypeString = …Run Code Online (Sandbox Code Playgroud) 嘿,以下存储访问查询在通过 VBA excel 运行时给出的 POEventCode 为“ NA ”,并且在直接从访问运行时给出正确的结果。为什么会出现这种异常情况?
SELECT D.[Event Code] & D.[Week Code] AS POEventCode, *
INTO A
FROM (SELECT IIf([Advertisement type]='Tabloide','TAB',
IIf([Advertisement type]='Flyer','FLY','NA')) AS [Event Code],
IIf(([Start Date]>[SD] And [Start Date]<[ED]),
[Month] & Right([WM_WK],2),'NA')
AS [Week Code], *
FROM [Feature A-Traits] AS C, [Event Code] AS B)
AS D
WHERE (D.[Week Code]) Not Like '*NA*'
And (D.[Event Code]) Not Like '*NA*';
Run Code Online (Sandbox Code Playgroud) 当我尝试在 64 位系统中安装 VS 项目时出现此错误。我已经下载并安装了AccessDatabaseEngine。还有其他任何方法可以做到这一点,我在我的应用程序中使用 MS Access(Office 2007)数据库。两个系统都使用x32 系统工具**。如果我正在安装 **AccessDatabaseEngine(x64),它会收到一个错误,您的系统包含(x32 系统工具)
public void EditUser(string id, string userid, string email, string password)
{
try
{
_dbConn.Open();
OleDbCommand updateCmd = new OleDbCommand("UPDATE LOGINS SET Username=?, Password=?, Email=? WHERE ID=?", _dbConn);
OleDbParameter param1 = new OleDbParameter("Username", userid);
OleDbParameter param2 = new OleDbParameter("Password", password);
OleDbParameter param3 = new OleDbParameter("Email", email);
OleDbParameter param4 = new OleDbParameter("ID", id);
param1.DbType = DbType.AnsiString;
param1.Direction = ParameterDirection.Input;
param2.DbType = DbType.AnsiString;
param2.Direction = ParameterDirection.Input;
param3.DbType = DbType.AnsiString;
param3.Direction = ParameterDirection.Input;
param4.DbType = DbType.AnsiString;
param4.Direction = ParameterDirection.Input;
updateCmd.Parameters.Add(param1);
updateCmd.Parameters.Add(param2);
updateCmd.Parameters.Add(param3);
updateCmd.Parameters.Add(param4);
int …Run Code Online (Sandbox Code Playgroud) 我想制定一个与 %Any Number% 不同的查询条件,其中包括数值以及任何包含数字的字符串。现在我用这个作为我的表达方式。它有效,但我想简化我的代码。
SELECT Distinct tblProductionTime.production_order_number
FROM tblProductionTime
GROUP BY tblProductionTime.production_order_number
HAVING (((tblProductionTime.production_order_number) Not ALike "%0%" And
(tblProductionTime.production_order_number) Not ALike "%1%" And
(tblProductionTime.production_order_number) Not ALike "%2%" And
(tblProductionTime.production_order_number) Not ALike "%3%" And
(tblProductionTime.production_order_number) Not ALike "%4%" And
(tblProductionTime.production_order_number) Not ALike "%5%" And
(tblProductionTime.production_order_number) Not ALike "%6%" And
(tblProductionTime.production_order_number) Not ALike "%7%" And
(tblProductionTime.production_order_number) Not ALike "%8%" And
(tblProductionTime.production_order_number) Not ALike "%9%"));
Run Code Online (Sandbox Code Playgroud) 我有一个轻量级的应用程序,将使用一些数据.我试图决定是否应该使用基于XML或只是包含一个mdb文件.
我有大数据集 - 10 000 条电话号码记录:
Phone_N
5656666666
6676767677
6767677777
5555555555
5555567888
6666777777
Run Code Online (Sandbox Code Playgroud)
我需要将其格式化为:
Phone_N
(565) 666-6666
(222) 767-3333
(676) 777-7777
Run Code Online (Sandbox Code Playgroud)
等等....
我的数据已经没有空格、“-”、“/”或任何其他字符。
它只需要格式化为适当的电话格式。
如果您能指出我正确的开始方向,那将非常有帮助。