SQL query using 2 different database engines - asp.net

I need to use the results from an Oracle query in a SQLServer query within ASP.NET. Can I do this without exporting the Oracle query results to a temp file, e.g. csv, and creating a new table in SQLServer using the csv file? Thanks!

There are probably several different ways to do this, including connecting the SQL Server to the Oracle server using Linked servers,
But if that's not possible for some reason, or if you need to use the Oracle resultset as well as the SQL Server resultset in your asp.net page, you can fill a DataSet with the Oracle query results, and send a DataTable as a table valued parameter to a stored procedure in the SQL Server.
Look at this page in MSDN, explaining how to use table valued parameters in sql server.
You can also look here for a step by step instruction on how to create and use table valued parameters in c#.

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is it possible to insert rows from a local table into a remote table in postgresql?

I have two postgresql databases, one on my local machine and one on a remote machine. If I'm connected to the local database (with psql), how do I execute a statement that inserts rows into a table on the remote database by selecting rows from a table on the local database? (I've seen this asked a handful of times, like here, here and here, but I haven't yet found a satisfactory answer or anyone saying definitively that it's not possible).
Specifically, assume I have tables remotetable and localtable, each with a single column columnA. I can run this statement successfully:
select dblink_exec('myconnection', 'insert into remotetable (columnA) values (1);');
but what I want to do is this:
select dblink_exec('myconnection', 'insert into remotetable (columnA) select columnA from localtable;');
But this fails with: relation "localtable" does not exist, presumably because localtable does not exist on the remote database.
Is it possible to do what I'm trying to do? If so, how do I indicate that localtable is, in fact, local? All of the examples I've seen for dblink-exec show inserts with static values, not with the results of a local query.
Note: I know how to query data from a remote table and insert into a local table, but I'm trying to move data in the other direction.
If so, how do I indicate that localtable is, in fact, local?
It's not possible because dblink acts as an SQL client to the remote server. That's why the queries sent through dblink_exec must be self-contained: they can do no more than any other query sent by any SQL application. Every object in the query is local to it from the server's perspective.
That is, unless you use another functionality, a Foreign-Data Wrapper with the postgres_fdw driver. This is a more sophisticated way to achieve server-to-server querying in which the SQL engine itself has this notion of foreign and local tables.

Invalid column definition error when using four part name to access Oracle DB as SQL Server linked server

I have setup a linked server in SQL Server 2008 R2 in order to access an Oracle 11g database. The MSDASQL provider is used to connect to the linked server through the Oracle Instant Client ODBC driver. The connection works well when using the OPENQUERY with the below syntax:
SELECT *
FROM OPENQUERY(LINKED_SERVER, 'SELECT * FROM SCHEMA.TABLE')
However, went I try to use a four part name using the below syntax:
SELECT *
FROM LINKED_SERVER..SCHEMA.TABLE
I receive the following error:
Msg 7318, Level 16, State 1, Line 1
The OLE DB provider "MSDASQL" for linked server "LINKED_SERVER" returned an invalid column definition for table ""SCHEMA"."TABLE"".
Does anyone have any insight on what my be causing the four part name query to fail while the OPENQUERY one works without any problems?
The correct path to follow is to use OPENQUERY function because your linked server is Oracle: the four name syntax will work fine for MSSQL servers, essentially because they understand T-SQL.
With very simple queries, a 4 part name can accidentally work but not often if you are in a real scenario. In your case, the SELECT * is returning all the columns, and in your case one of the column definition is not compatible with SQL Server. Try another table or try to select a single simple column (e.g. a CHAR or a NUMBER), maybe it will work without problem.
In any case, using distributed queries can be tricky sometime. Database itself does some optimizations before executing commands, so it is important for the database to know what it can do and what it can't. If the DB thinks the linked server is MSSQL, it will take some action that may not work with Oracle.
When using four part name syntax with a linked DB different from MSSQL, you will have other problems as well, for example using database builtin functions (i.e. to_date() Oracle function will not work because MSSQL would want to use its own convert() function, and so on).
So again, if the linked server is not a MSSQL, the right choice is to use OPENQUERY and passing it a query that use a syntax valid against the linked server SQL dialect.
If you use the OLEDB provider for Oracle you can query without using openquery

Trace the Cause for update of Sql Table

I have a table Product which have Quantity column, This table get updated thru .net application using Stored procedure based on flag variable. Now im having problem reported from user that even though the flag variable is not set table is getting updated with new values.
Now i need to isolated the cause for the issue.How will i check which update and through which application this table is getting modified. I have no idea about it.
What is the best approach to resolve this issue?
Assuming you are using SQL Server:
You can monitor calls to SQL Server using SQL Server Profiler. You can setup a filter to monitor queries affecting the Product table. The log will show what the query looked like, when the query was executed, the database user executing the query, the name of the application (if that is specified in the connection string) and a bunch of other things.

How do I import xml data into a sql server database table in Windows form using c#?

I wanted to display Xml data into the sql server database table.
First, I displayed the Xml data using the console application at run time, but now I want to store that XMl data into the database table.
How can I do this?
Himanshu Negi
Well, your XML is supposed to be a string (or it can easily be converted to).
So you can do this:
INSERT INTO your_table (your_col)
SELECT xml_str
I'm assuming you know how to connect to your db and run a SqlCommand after the connection is established...

Bulk Insert multiple records and get identity for all using ADO.NET

I want to batch insert multiple records in sql server database using ADO.NET command/sqldataadapter and get identity value generated for all the rows in a single database trip.
What are my options?
If you're using either, SQL server 2005 and 2008 add support for the OUTPUT clause, which enables you to return a result-set from an UPDATE/INSERT/DELETE statement.

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