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It's a problem with ODBC that I've seen before.
ODBC configurations are often cached in memory. They're read once and the settings are held in memory until the application exits. This is to improve performance (marginally) be not re-reading the same data from the same text file over and over and over again.
The down side is the problem you've run into. One solution would be to create a new DSN on-the-fly for each connection, with unique names, and use the newly created DSN each time. The only time you'd have caching headaches this way is if you reuse the same DSN name for two different connections.
Grim (aka Toby) MCDBA, MCSD, MCP+SB
SELECT * FROM user WHERE clue IS NOT NULL
GO
(0 row(s) affected)
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Im making a program wherein data is to be retrieved based from the database being selected. My list of database files use the same DataSourceName. Im using SQLConfigDataSource function. And ODBC_CONFIG_SYS_DSN as one of its parameters since only the DBQ attribute or the database path is changing. When I select one database file then, loads it, the data retrieved is correct. However, when I select another database file, the data retrieved is the same as the data from the first database file I selected. This means that my recordset was not refreshed. But when I checked the ODBC Administrator, it is updated based on my selection. My problem is I dont know if Im missing other functions or include files in order to refresh the recordset. I tried calling the GetDefaultConnect() function before opening the recordset but the result is still the same... please help me with this problem. Im using the CRecordset....
Does anyone care to help? pls.............
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Hi :
I need to store and retreive a BLOB from and into an Oracle 9i DataBase.
I'm developing an ASP.NET application an i need to display in a web form an image stote as a BLOB.
Does any one have an idea of HOW-TO do that
if you have C# code example i'll really apreciate it!!
thanks
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Using VS 2003
When I select the proper DataSource and DisplayMember in the property window of VS for a combo box does anyone know why when I run the local application clicking on the combo box doesn't provide the actual drop down box NOTE: if I select a different table in that same DS it works I have previewed data, schema, keys, etc
************ Details Follow *********************
1. I Connect to a MS-Access dB, create a DataAdapter (DA1) for Table1 and a DateSet (DS) with Table1
2. I populate a Datagrid and associated Textboxes (TB -Text) w/ the DS.DA1 - all O’K
3. I then add some Combo boxes (CB) to form
4. I drag and drop a Table2 (the dropdown choices for the CB) to create DA2
5. I Configure DA2, "Generate DS" for DA2 using the “Existing DS” and Preview data. The DS Schema shows DA1 and DA2 – all appears O.k.
6. For the CB, I "select" from dropdown DS.DA2 (ie Table2) as the DataSource and a given Table2 column for the DisplayMember
When I run the program no CB drop down available from DS.DA2 (table2). Of course, if I select DS.DA1 for the DataSource it works perfectly. Any Ideas?
Steve
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I have a database under development. For testing I created a couple of tables with the user account 'test_schema' which is their owner.
If I use the SQL below to query the structure of the table as 'sa' then some of the fields come back as null whereas if I perform the same query as 'test_schema' I get all the fields correctly.
DECLARE @table_name varchar(128);
SET @table_name = 'single_pkey';
SELECT cols.COLUMN_NAME as column_name,
cols.DATA_TYPE as type,
cols.CHARACTER_MAXIMUM_LENGTH AS length,
CASE WHEN cols.IS_NULLABLE = 'No' THEN 0 ELSE 1 END as is_nullable,
CASE WHEN pks.column_name IS NULL THEN NULL ELSE cols.ORDINAL_POSITION END AS primary_key,
cols.ORDINAL_POSITION as position,
pks.column_name as pks_column_name -- For testing
FROM INFORMATION_SCHEMA.COLUMNS cols
LEFT OUTER JOIN (SELECT kcu.COLUMN_NAME as column_name
FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE as kcu
INNER JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS as tc
ON kcu.CONSTRAINT_NAME = tc.CONSTRAINT_NAME
WHERE tc.TABLE_NAME = @table_name
AND CONSTRAINT_TYPE='PRIMARY KEY') as pks
ON pks.column_name = cols.COLUMN_NAME
WHERE TABLE_NAME = @table_name
ORDER BY cols.ORDINAL_POSITION
As the 'sa' user the [primary_key] column in the result set is always NULL when the owner if 'test_schema'.
Does anyone have any ideas that might help me out?
[If I've missed off some important piece of information then let me know - I'm sure I am just missing something obvious, but I just can't see it right now]
"If a man empties his purse into his head, no man can take it away from him, for an investment in knowledge pays the best interest." -- Joseph E. O'Donnell
The Second EuroCPian Event will be in Brussels on the 4th of September
Can't manage to P/Invoke that Win32 API in .NET? Why not do interop the wiki way!
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In SQL 2000 it is possible that there are multiple tables called the same thing, owned by different users. Is that the case in your database?
my blog
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Not in this particular database. Although for other parts of the system (there will be lots of databases) that may be the case - So, I'll have to take that into account elsewhere.
"If a man empties his purse into his head, no man can take it away from him, for an investment in knowledge pays the best interest." -- Joseph E. O'Donnell
The Second EuroCPian Event will be in Brussels on the 4th of September
Can't manage to P/Invoke that Win32 API in .NET? Why not do interop the wiki way!
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Hi..
In my form, I have three combo boxes, one Add button one Save button
and a listview.
Step 1:The comboboxes is being populated by a dataset.
Step 2: On clicking the add button, the listview should get populated with the contents of the combobox.text.
I can repeat Step2 a number of times, each time selecting a different value in the comboBox and adding in the ListView
Step 3: on clicking the Save button, all the data in the listview should be saved in a database.
How will I accomplish this the task? How do i save the Columns and fields of the ListView into a dataset
plz help with code or explanation
Thanks
Breath dot net
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First off, you need to decide which database utilities you are planning to code with, that is, are you going to use ADO, DAO, OLEDB, etc. ADO is usually meant for VB users, but I find myself using it without too much hassel in VC++. DAO is meant more for Access users and OLEDB I believe is Active Xish. There is also the cut and dry ODBC which has been around longer. Anyways, tons of material here on CodeProject to help you figure out what is the best for you. After deciding that then move onto your application. There is a wonderful ADO wrapper class here on CodeProject I use. I think there are few others for DAO and ODBC. Get familiar with those.
To save data into a database the following psuedocode can be followed.
OpenDatabaseConnection(...)
Recordset = OpenRecordset(...)
Recordset.AddNew(...)
Recordset.SetFieldValue(Field /*database field*/, Value/*the value to go into that field*/);
Recordset.Update(...)
I would check out the examples here on CodeProject going under the link http://www.codeproject.com/database/
TONS of examples with code that should answer most of your questions.
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hi code guys!
I've a web database LOGINS(ms access).
DSN is DSN_pkbiz
I want to access db from within c# app through ODBC.NET.
pls tell me about the exact connection string.
the rest I'll do.
Time is a good teacher but unfortunately it kills all his students.
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Hi there....
Friends is this possible to get Mysql free of charge .
And from where i get the software.
Help will be appriciated .
Thanks
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This can be easily be found using Google...
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I am just new in the field .So please tell me that whic version is better for me and which mirror is better i am living in Pakistan .
Thanks
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g-o-o-g-l-e: (v) To run something or someone through Google, the first step in researching anything - http://www.lostremote.com/story/jargon.htm
my blog
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Ok, does anyone know how to retrieve Data that is generated from a Stored proc into an ADO.NET DataSet or DataTable? This used to be very easy in VB6...  I just need a sample to lead me on the right track.
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In the stored procedure you just SELECT the relevant data. In the .NET application open a SqlConnection, create a SqlCommand to call the Stored Procedure and then call SqlCommand.ExecuteQuery() to get a DataReader to extract it*
Does this help?
*You can also uses crazy things like DataAdapters and DataSets, but y'know I don't really like them
"If a man empties his purse into his head, no man can take it away from him, for an investment in knowledge pays the best interest." -- Joseph E. O'Donnell
The Second EuroCPian Event will be in Brussels on the 4th of September
Can't manage to P/Invoke that Win32 API in .NET? Why not do interop the wiki way!
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Sorry, I should have been more specific. Unfortunately, I do need to get this data into a DataTable or DataSet. Anyone have an idea? I know the DataAdapter uses a DataReader internally, but I don't know how I could implement this...I'm sure it would be super difficult.
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In the "Server Explorer" window select the connection to your database that contains the stored procedure and drag it to your form. This will create a SqlConnection object and a SqlCommand object, for example conn and cmd.
Then you can fill your DataSet with the following commands:
conn.Open();
SqlDataAdapter dataAdapter = new SqlDataAdapter(cmd);
DataSet dataset = new DataSet("datasetName");
dataAdapter.Fill(dataset);
conn.Close();
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Yeah, that's not going to work either, tried that before...
The problem is that the Stored Proc is Dynamically creating Columns and Data depending on what Parameters you pass to it. Even in the Designer, I can't get it to Generate a DataSet because ADO.NET what hard-defined structures of Data when working with the Designer. However, I can run the Data Preview and it works fine, but that is because in the "Preview" mode, the data is being retrieved through a DataReader, not a DataTable.
Why can't the DataCommand Object just return a DataTable like it did in VB6!? 
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public static DataSet GetEventList(
int activeState,
int eventId,
int eventDateStatus,
DateTime eventDateStart,
DateTime eventDateEnd,
int createDateStatus,
DateTime createDateStart,
DateTime createDateEnd,
int ntdStatus,
int eventTypeId,
string firstName,
string lastName)
{
DataSet ds = null;
SqlCommand cmd = null;
SqlDataAdapter da = null;
SqlConnection conn = GetConnection();
if (conn != null)
{
try
{
cmd = new SqlCommand("EventListGet",conn);
cmd.CommandType = CommandType.StoredProcedure;
SqlParameter p = cmd.Parameters.Add("@ActiveState",SqlDbType.Int);
p.Value = activeState;
p = cmd.Parameters.Add("@EventId",SqlDbType.Int);
p.Value = eventId;
p = cmd.Parameters.Add("@EventDateStatus",SqlDbType.Int);
p.Value = eventDateStatus;
p = cmd.Parameters.Add("@EventDateStart",SqlDbType.DateTime);
p.Value = eventDateStart;
p = cmd.Parameters.Add("@EventDateEnd",SqlDbType.DateTime);
p.Value = eventDateEnd;
p = cmd.Parameters.Add("@CreateDateStatus",SqlDbType.Int);
p.Value = createDateStatus;
p = cmd.Parameters.Add("@CreateDateStart",SqlDbType.DateTime);
p.Value = createDateStart;
p = cmd.Parameters.Add("@CreateDateEnd",SqlDbType.DateTime);
p.Value = createDateEnd;
p = cmd.Parameters.Add("@NTDState",SqlDbType.Int);
p.Value = ntdStatus;
p = cmd.Parameters.Add("@EventTypeId",SqlDbType.Int);
p.Value = eventTypeId;
p = cmd.Parameters.Add("@FirstName",SqlDbType.VarChar,50);
p.Value = firstName;
p = cmd.Parameters.Add("@LastName",SqlDbType.VarChar,50);
p.Value = lastName;
da = new SqlDataAdapter(cmd);
ds = new DataSet();
da.Fill(ds);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message,"Load Event List Failed");
if (ds != null)
{
ds.Dispose();
ds = null;
}
}
finally
{
if (da != null) da.Dispose();
if (cmd != null) cmd.Dispose();
if (conn != null) conn.Close();
}
}
return ds;
}
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Ok, this is very similar to what I tried. Do you think it matters if the Stored Proc is creating and using a Temporary Table (ex. ##TempTable)? I get errors on my Temp Table in the Designer. It doesn't make any sense because I can run this in the Query Analyzer without fail every time!
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Are you sure the table is being DROP'ed properly at the end of your SP?
What is the error you are getting?
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Has anyone experienced a problem with using an odbc driver where it retrieves some records without any problems, but other records are coming back as it was from a different world?
Here's the layout, I'm reading data from a dataflex table using Connx ODBC driver. When I run a simple SQL query statement on a query tool, for ex, Select * From tablename I noticed half the rows are garbage. Here's the funny part, I run a report, Cystal Reports, using their own driver to connect to the database and all the rows are fine.
Any advice would be helpful. Thanks.
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