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Pythonnet Runtime Error using C# dll (Database Incompatibility)

enter image description hereI am using a C# dll using pythonnet on python 2.7.13 (which uses other dll files and .mdb database files) to make some technical calculations. This dll files does not have a good documentation (only namespaces, class and method names). Well the program in most PC Works Fine but in all office computers it throws a runtime Error from Dll files (my doubt is connection with database). This dll files are compiled to target .NET 4.0 (in office computers is installed .NET 4.7.1 or other versions newer than 4.0) and EntityFramework is also being used (programs target 5.0 and this is a dll file in program folder, but in office computers is installed EntityFramework 6.2 tool). Microsoft database Engine 2010 is also installed in those computers.
In every other computer that I have tested the program it works perfectly. In office computers I found a group of input data for which program works, but anyway this is not correct because it should work also for the default data.
To make tests in office computers I have compiled python code using PyInstaller (I repeat, compiled version work fine in other PCs).
I am using .NET Reflector to decompile dll files and programs Exception to find the Error. The method that throws Exception is in the following code.
Thanks in advance!
public int LoadRanghiAmmessi(int[] vRanghi, string geometria)
{
int index = 0;
CrConnection connection = new CrConnection(this.PathDB);
string query = "SELECT * FROM RanghiAmmessi WHERE (Geometria='" + geometria + "') ORDER BY NRanghi";
OleDbDataReader recordset = connection.GetRecordset(query, #"\Coils.mdb;");
if (!recordset.HasRows)
{
if (recordset != null)
{
recordset.Close();
}
query = "SELECT * FROM RanghiAmmessi WHERE (Geometria='*') ORDER BY NRanghi";
recordset = connection.GetRecordset(query, #"\Coils.mdb;");
while (recordset.Read())
{
vRanghi[index] = int.Parse(recordset["NRanghi"].ToString());
index++;
}
if (recordset != null)
{
recordset.Close();
}
}
return index;
}
public OleDbDataReader GetRecordset(string query, string NomeDB)
{
string connectionString = "Provider=Microsoft.JET.OLEDB.4.0;Data Source=" + this.PathDB + NomeDB + "Jet OLEDB:Database Password=123456";
this.ChiudiConnessioni();
this.conn = new OleDbConnection(connectionString);
OleDbCommand command = new OleDbCommand(query, this.conn);
try
{
this.ApriConnessione();
return command.ExecuteReader();
}
catch (Exception exception)
{
exception.Message.ToString();
this.ChiudiConnessioni();
return null;
}
}

After many tests I found out that the program is working also in other PC after declaring some objects like function parameters and after compiling running the program as compatible with Windows 7. Before the objects were created like variables and those variables were passed as parameters, (in this case, reasonably the first thought is that the problem is "pass by reference" mechanism and that some values are not inserted in the right mode, but this is not the case because:
- the same exactly code did function very well in most PC (compatibility
problem)
- the same exactly mechanism is used to specify the objects attributes and
to make calculations
In this conditions I would say that it is not clear where the problem was. In the first version installing the SQL Server Express made possible for the program to work well even without last modifications.

Umm... given the details that it works fine on "Other PC", I am guessing that the problem is your so-called database. I don't see in any way, however, how anyone could be certain at what the problem is until it is solved.

C# Not saving data in MS Access Database [duplicate]

I have following C# code in a console application.
Whenever I debug the application and run the query1 (which inserts a new value into the database) and then run query2 (which displays all the entries in the database), I can see the new entry I inserted clearly. However, when I close the application and check the table in the database (in Visual Studio), it is gone. I have no idea why it is not saving.
using System;
using System.Collections.Generic;
using System.Data.Entity;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Data.SqlServerCe;
using System.Data;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
try
{
string fileName = "FlowerShop.sdf";
string fileLocation = "|DataDirectory|\\";
DatabaseAccess dbAccess = new DatabaseAccess();
dbAccess.Connect(fileName, fileLocation);
Console.WriteLine("Connected to the following database:\n"+fileLocation + fileName+"\n");
string query = "Insert into Products(Name, UnitPrice, UnitsInStock) values('NewItem', 500, 90)";
string res = dbAccess.ExecuteQuery(query);
Console.WriteLine(res);
string query2 = "Select * from Products";
string res2 = dbAccess.QueryData(query2);
Console.WriteLine(res2);
Console.ReadLine();
}
catch (Exception e)
{
Console.WriteLine(e);
Console.ReadLine();
}
}
}
class DatabaseAccess
{
private SqlCeConnection _connection;
public void Connect(string fileName, string fileLocation)
{
Connect(#"Data Source=" + fileLocation + fileName);
}
public void Connect(string connectionString)
{
_connection = new SqlCeConnection(connectionString);
}
public string QueryData(string query)
{
_connection.Open();
using (SqlCeDataAdapter da = new SqlCeDataAdapter(query, _connection))
using (DataSet ds = new DataSet("Data Set"))
{
da.Fill(ds);
_connection.Close();
return ds.Tables[0].ToReadableString(); // a extension method I created
}
}
public string ExecuteQuery(string query)
{
_connection.Open();
using (SqlCeCommand c = new SqlCeCommand(query, _connection))
{
int r = c.ExecuteNonQuery();
_connection.Close();
return r.ToString();
}
}
}
EDIT: Forgot to mention that I am using SQL Server Compact Edition 4 and VS2012 Express.

It is a quite common problem. You use the |DataDirectory| substitution string. This means that, while debugging your app in the Visual Studio environment, the database used by your application is located in the subfolder BIN\DEBUG folder (or x86 variant) of your project. And this works well as you don't have any kind of error connecting to the database and making update operations.
But then, you exit the debug session and you look at your database through the Visual Studio Server Explorer (or any other suitable tool). This window has a different connection string (probably pointing to the copy of your database in the project folder). You search your tables and you don't see the changes.
Then the problem get worse. You restart VS to go hunting for the bug in your app, but you have your database file listed between your project files and the property Copy to Output directory is set to Copy Always. At this point Visual Studio obliges and copies the original database file from the project folder to the output folder (BIN\DEBUG) and thus your previous changes are lost.
Now, your application inserts/updates again the target table, you again can't find any error in your code and restart the loop again until you decide to post or search on StackOverflow.
You could stop this problem by clicking on the database file listed in your Solution Explorer and changing the property Copy To Output Directory to Copy If Newer or Never Copy. Also you could update your connectionstring in the Server Explorer to look at the working copy of your database or create a second connection. The first one still points to the database in the project folder while the second one points to the database in the BIN\DEBUG folder. In this way you could keep the original database ready for deployment purposes and schema changes, while, with the second connection you could look at the effective results of your coding efforts.
EDIT Special warning for MS-Access database users. The simple act of looking at your table changes the modified date of your database ALSO if you don't write or change anything. So the flag Copy if Newer kicks in and the database file is copied to the output directory. With Access better use Copy Never.

Committing changes / saving changes across debug sessions is a familiar topic in SQL CE forums. It is something that trips up quite a few people. I'll post links to source articles below, but I wanted to paste the answer that seems to get the best results to the most people:
You have several options to change this behavior. If your sdf file is part of the content of your project, this will affect how data is persisted. Remember that when you debug, all output of your project (including the sdf) if in the bin/debug folder.
You can decide not to include the sdf file as part of your project and manage the file location runtime.
If you are using "copy if newer", and project changes you make to the database will overwrite any runtime/debug changes.
If you are using "Do not copy", you will have to specify the location in code (as two levels above where your program is running).
If you have "Copy always", any changes made during runtime will always be overwritten
Answer Source
Here is a link to some further discussion and how to documentation.

sqlclient fails to execute anything except select statements [duplicate]

I have following C# code in a console application.
Whenever I debug the application and run the query1 (which inserts a new value into the database) and then run query2 (which displays all the entries in the database), I can see the new entry I inserted clearly. However, when I close the application and check the table in the database (in Visual Studio), it is gone. I have no idea why it is not saving.
using System;
using System.Collections.Generic;
using System.Data.Entity;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Data.SqlServerCe;
using System.Data;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
try
{
string fileName = "FlowerShop.sdf";
string fileLocation = "|DataDirectory|\\";
DatabaseAccess dbAccess = new DatabaseAccess();
dbAccess.Connect(fileName, fileLocation);
Console.WriteLine("Connected to the following database:\n"+fileLocation + fileName+"\n");
string query = "Insert into Products(Name, UnitPrice, UnitsInStock) values('NewItem', 500, 90)";
string res = dbAccess.ExecuteQuery(query);
Console.WriteLine(res);
string query2 = "Select * from Products";
string res2 = dbAccess.QueryData(query2);
Console.WriteLine(res2);
Console.ReadLine();
}
catch (Exception e)
{
Console.WriteLine(e);
Console.ReadLine();
}
}
}
class DatabaseAccess
{
private SqlCeConnection _connection;
public void Connect(string fileName, string fileLocation)
{
Connect(#"Data Source=" + fileLocation + fileName);
}
public void Connect(string connectionString)
{
_connection = new SqlCeConnection(connectionString);
}
public string QueryData(string query)
{
_connection.Open();
using (SqlCeDataAdapter da = new SqlCeDataAdapter(query, _connection))
using (DataSet ds = new DataSet("Data Set"))
{
da.Fill(ds);
_connection.Close();
return ds.Tables[0].ToReadableString(); // a extension method I created
}
}
public string ExecuteQuery(string query)
{
_connection.Open();
using (SqlCeCommand c = new SqlCeCommand(query, _connection))
{
int r = c.ExecuteNonQuery();
_connection.Close();
return r.ToString();
}
}
}
EDIT: Forgot to mention that I am using SQL Server Compact Edition 4 and VS2012 Express.

It is a quite common problem. You use the |DataDirectory| substitution string. This means that, while debugging your app in the Visual Studio environment, the database used by your application is located in the subfolder BIN\DEBUG folder (or x86 variant) of your project. And this works well as you don't have any kind of error connecting to the database and making update operations.
But then, you exit the debug session and you look at your database through the Visual Studio Server Explorer (or any other suitable tool). This window has a different connection string (probably pointing to the copy of your database in the project folder). You search your tables and you don't see the changes.
Then the problem get worse. You restart VS to go hunting for the bug in your app, but you have your database file listed between your project files and the property Copy to Output directory is set to Copy Always. At this point Visual Studio obliges and copies the original database file from the project folder to the output folder (BIN\DEBUG) and thus your previous changes are lost.
Now, your application inserts/updates again the target table, you again can't find any error in your code and restart the loop again until you decide to post or search on StackOverflow.
You could stop this problem by clicking on the database file listed in your Solution Explorer and changing the property Copy To Output Directory to Copy If Newer or Never Copy. Also you could update your connectionstring in the Server Explorer to look at the working copy of your database or create a second connection. The first one still points to the database in the project folder while the second one points to the database in the BIN\DEBUG folder. In this way you could keep the original database ready for deployment purposes and schema changes, while, with the second connection you could look at the effective results of your coding efforts.
EDIT Special warning for MS-Access database users. The simple act of looking at your table changes the modified date of your database ALSO if you don't write or change anything. So the flag Copy if Newer kicks in and the database file is copied to the output directory. With Access better use Copy Never.

Committing changes / saving changes across debug sessions is a familiar topic in SQL CE forums. It is something that trips up quite a few people. I'll post links to source articles below, but I wanted to paste the answer that seems to get the best results to the most people:
You have several options to change this behavior. If your sdf file is part of the content of your project, this will affect how data is persisted. Remember that when you debug, all output of your project (including the sdf) if in the bin/debug folder.
You can decide not to include the sdf file as part of your project and manage the file location runtime.
If you are using "copy if newer", and project changes you make to the database will overwrite any runtime/debug changes.
If you are using "Do not copy", you will have to specify the location in code (as two levels above where your program is running).
If you have "Copy always", any changes made during runtime will always be overwritten
Answer Source
Here is a link to some further discussion and how to documentation.

How do I use C# and ADO.NET to query an Oracle table with a spatial column of type SDO_GEOMETRY?

My development machine is running Windows 7 Enterprise, 64-bit version. I am using Visual Studio 2010 Release Candidate. I am connecting to an Oracle 11g Enterprise server version 11.1.0.7.0. I had a difficult time locating Oracle client software that is made for 64-bit Windows systems and eventually landed here to download what I assume is the proper client connectivity software. I added a reference to "Oracle.DataAccess" which is version 2.111.6.0 (Runtime Version is v2.0.50727). I am targeting .NET CLR version 4.0 since all properties of my VS Solution are defaults and this is 2010 RC. I was then able to write a console application in C# that established connectivity, executed a SELECT statement, and properly returned data when the table in question does NOT contain a spatial column. My problem is that this no longer works when the table I query has a column of type SDO_GEOMETRY in it.
Below is the simple console application I am trying to run that reproduces the problem. When the code gets to the line with the "ExecuteReader" command, an exception is raised and the message is "Unsupported column datatype".
using System;
using System.Data;
using Oracle.DataAccess.Client;
namespace ConsoleTestOracle
{
class Program
{
static void Main(string[] args)
{
string oradb = string.Format("Data Source={0};User Id={1};Password={2};",
"hostname/servicename", "login", "password");
try
{
using (OracleConnection conn = new OracleConnection(oradb))
{
conn.Open();
OracleCommand cmd = new OracleCommand();
cmd.Connection = conn;
cmd.CommandText = "select * from SDO_8307_2D_POINTS";
cmd.CommandType = CommandType.Text;
OracleDataReader dr = cmd.ExecuteReader();
}
}
catch (Exception e)
{
string error = e.Message;
}
}
}
}
The fact that this code works when used against a table that does not contain a spatial column of type SDO_GEOMETRY makes me think I have my windows 7 machine properly configured so I am surprised that I get this exception when the table contains different kinds of columns. I don't know if there is some configuration on my machine or the Oracle machine that needs to be done, or if the Oracle client software I have installed is wrong, or old and needs to be updated.
Here is the SQL I used to create the table, populate it with some rows containing points in the spatial column, etc. if you want to try to reproduce this exactly.
SQL Create Commands:
create table SDO_8307_2D_Points (ObjectID number(38) not null unique, TestID number, shape SDO_GEOMETRY);
Insert into SDO_8307_2D_Points values (1, 1, SDO_GEOMETRY(2001, 8307, null, SDO_ELEM_INFO_ARRAY(1, 1, 1), SDO_ORDINATE_ARRAY(10.0, 10.0)));
Insert into SDO_8307_2D_Points values (2, 2, SDO_GEOMETRY(2001, 8307, null, SDO_ELEM_INFO_ARRAY(1, 1, 1), SDO_ORDINATE_ARRAY(10.0, 20.0)));
insert into user_sdo_geom_metadata values ('SDO_8307_2D_Points', 'SHAPE', SDO_DIM_ARRAY(SDO_DIM_ELEMENT('Lat', -180, 180, 0.05), SDO_DIM_ELEMENT('Long', -90, 90, 0.05)), 8307);
create index SDO_8307_2D_Point_indx on SDO_8307_2D_Points(shape) indextype is mdsys.spatial_index PARAMETERS ('sdo_indx_dims=2' );
Any advice or insights would be greatly appreciated. Thank you.

Here is a link to a post with a sample app using C# and ODP.net to access spatial types.
http://www.orafaq.com/forum/mv/msg/27794/296419/0/#msg_296419
There is also a sample here about using XML to select the spatial types:
http://forums.oracle.com/forums/thread.jspa?threadID=241076

Paradox Tables in C#

I'm trying to read a Paradox 5 table into a dataset or simular data structure with the view to putting it into an SQL server 2005 table. I've trawled google and SO but with not much luck. I've tried ODBC:
public void ParadoxGet()
{
string ConnectionString = #"Driver={Microsoft Paradox Driver (*.db )};DriverID=538;Fil=Paradox 5.X;DefaultDir=C:\Data\;Dbq=C:\Data\;CollatingSequence=ASCII;";
DataSet ds = new DataSet();
ds = GetDataSetFromAdapter(ds, ConnectionString, "SELECT * FROM Growth");
foreach (String s in ds.Tables[0].Rows)
{
Console.WriteLine(s);
}
}
public DataSet GetDataSetFromAdapter(DataSet dataSet, string connectionString, string queryString)
{
using (OdbcConnection connection = new OdbcConnection(connectionString))
{
OdbcDataAdapter adapter = new OdbcDataAdapter(queryString, connection);
connection.Open();
adapter.Fill(dataSet);
connection.Close();
}
return dataSet;
}
This just return the error
ERROR [HY000] [Microsoft][ODBC Paradox Driver] External table is not in the expected format.
I've also tired OELDB (Jet 4.0) but get the same External table is not in the expected format error.
I have the DB file and the PX (of the Growth table) in the Data folder... Any help would be much appriciated.

I've had the same error. It appeared when I started my C# project on Win2008 64 (previos OS was Win2003 32). Also I found out that it worked fine in console apps and gave different errors in winforms. It seems that problem comes from the specifics of 32 ODBC driver working on 64-bit systems.
My solution was:
// Program.cs
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
// it is important to open paradox connection before creating
// the first form in the project
if (!Data.OpenParadoxDatabase())
return;
Application.Run(new MainForm());
}
The connectionstring is common:
string connStr = #"Driver={{Microsoft Paradox Driver (*.db )}};DriverID=538;
Fil=Paradox 7.X;DefaultDir=C:\\DB;Dbq=C:\\DB;
CollatingSequence=ASCII;";
After opening connection you may close it in any place after creating first Form (if you need to keep DB closed most of time), for example:
private void MainForm_Load(object sender, EventArgs e)
{
Data.CloseParadoxDatabase();
}
After doing that you may open and close connection every time you want during execution of your application and you willn't get any exceptions.

Maybe this will help you out,
http://support.microsoft.com/support/kb/articles/Q237/9/94.ASP?LN=EN-US&SD=SO&FR=1
http://support.microsoft.com/support/kb/articles/Q230/1/26.ASP
It appears that the latest version of the Microsoft Jet Database Engine
(JDE) does not fully support Paradox unless the Borland Database Engine
(BDE) is also installed.

Try to Run all The Applications with the "Run As Administrator" privileges especially run the VS.NET with "Run As Administrator "... and I am sure your problem get solved

This isn't an answer, but more of a question: any particular reason you're trying to use C# to do the data manipulation as opposed to using SQL Server tools to load the data directly? Something like DTS or SSIS would seem like a better tool for the job.

Thanks, I'll give that a try. I wanted to use C# so I can put it on some web pages without the extra set of putting it in SQL server.