What is difference in adodb and oledb? - ado.net

What is the difference between adodb and oledb?
What is the relation between these two?
Where does ado.net stands in context of adodb and oledb?

Adodb (ActiveX Data Objects DB) is an API layer over OLE DB. It works well with MS-based databases such as Sql Server, providing a consistent API and optimizations. That being said you can use ADODB to connect with non-MS data sources as well but that would mean that you will require an OLEDB/ODBC Provider for the data source.
In simpler terms, to connect to any data source you need a driver. Here are a couple of common scenarios to think of:
ADODB for Data Source that has ODBC Driver Only - ADODB uses OLEDB Provider for ODBC which loads ODBC Driver which then connects to Data Source.
ADODB for Data Source with OLEDB Driver (like SQL Server) - ADODB uses OLEDB Provider for SQL Server to talk directly with DB.
Oledb (Object Linking and Embedding DB) is a standard format supported by a large number of dbs, so you can connect to oracle, db2 etc. using Oledb. You can also use OLEDB directly to connect to Sql Server but the API is messier as compared to a adodb connection which is optimized to work with Sql Server and MS Access.
ADO.Net is a .Net based db connection "architecture". In ADO.Net there's a library for Oledb - System.Data.OledbClient. Adodb has been replaced/upgraded and ADO.Net now uses the System.Data.SqlClient library for MS-based databases/data providers.

ADO is a COM-based library for accessing databases.
OleDB and ODBC are standards for communicating with databases.
ADO uses the OleDB to talk to any database that exposes an OleDB driver.
There is also an OleDB driver that can wrap any ODBC driver. Thus ADO can also talk to any database that exposes an ODBC driver.
ADO.NET (a.k.a. System.Data) is a .NET based library for accessing databases.
ADO.NET has built-in support for SQL Server, OleDB, and ODBC
Third parties can expose their database to ADO.NET by building a ADO.NET compatible library
Third parties can also expose their database to ADO.NET by offering an OleDB or ODBC driver

Related

How to access mongodb data from Oracle server?

We are using Oracle server and we need to fetch data from MongoDB. As RHEL 7 is supported for installing MongoDB drivers, and the one we use is RHEL 6.9. So drivers are not installed and dblink was not created. We are looking for other options to access this MongoDB server from Oracle server.
Please need help here.
This will be a challenge because Oracle is a relational database whereas MongoDB is "NoSQL". A native connection is not possible.
Look for a MongoDB ODBC Driver, e.g.
MongoDB ODBC Driver
Progress DataDirect ODBC Driver for MongoDB
devart ODBC Driver for MongoDB
CData MongoDB ODBC Driver
easysoft MongoDB ODBC Driver
Once you installed one of them, use the Oracle Database Gateway for ODBC to access the MongoDB via the ODBC driver.
The configuration of this can be tricky, but it should be possible.
Almost any popular programming language is able to connect to an Oracle database as well to connect to MongoDB. So, you can write a program/script which copies data from one database to the other. However, if you like to use direct connection (i.e. database link in Oracle) the you have to use one of these ODBC driver.
In combination with the Oracle Gateway for ODBC, you solve this problem via any of the following solutions:
ODBC or JDBC (via ODBC-to-JDBC Bridge) Drivers and Oracle's Database Integrator for ODBC
ODBC- and/or JDBC-compliant Data Virtualization Platform
ODBC Driver and Oracle Data Integration (ODI) Gateway
Attach Oracle to MongoDB Driver. You can use a native JDBC driver, or a JDBC-to-ODBC Bridge Driver plus a native ODBC driver
Perform your Data Manipulation operations via ODI
OpenLink JDBC-to-ODBC Bridge Drivers provide enhanced DBMS virtualization that increases compatibility between JDBC client apps and 3rd party ODBC Drivers.
Data Virtualization Platform Solution
Here's how it works, given that you have ODBC access to each of Oracle and MySQL Database Management Systems (DBMS), using either a native ODBC Driver or a native JDBC Driver with an OBDC-to-JDBC Bridge:
Attach the Data Virtualization Platform to the MongoDB instance
Attach the Data Virtualization Platform to the Oracle instance
Perform your Data Manipulation (DML) operations on Data managed by either DBMS, as though they were in local tables in the Data Virtualization Layer
Our Virtuoso Multi-Model Database Management and Virtualization Platform is an example of a Data Virtualization solution that operates in the manner described above.
Related
Data Virtualization for Beginners
OpenLink ODBC-to-ODBC Bridge Drivers — increase compatibility of third party ODBC Drivers with Oracle's ODBC Gateway
OpenLink JDBC-to-ODBC Bridge Drivers — enable use of third party ODBC Drivers with Oracle's ODI middleware
OpenLink JDBC-to-JDBC Bridge Drivers — increase compatibility of third party JDBC Drivers with Oracle's ODI middleware
OpenLink ODBC-to-JDBC Bridge Drivers — enable use of third party JDBC Drivers with Oracle's ODBC Gateway
Using Oracle's ODI and the OpenLink JDBC-to-ODBC Bridge to connect to Microsoft Excel data sources
Virtuoso Data Virtualization Platform

Oracle SQL Developer database diff doesn’t list my connections

I’m trying to perform a Diff on two DB2 schema’s and when I try to select my source and destination connections it doesn’t list my NEW connection. I’m using latest version. I can connect to DB2 manually and query as well, but just can’t sect that connection during database Diff.
Where are the connections saved in sql
Developer?
That feature is reserved for Oracle Database connections.
DB2 connectivity is provided for migrations to Oracle only.
We have limited support for DB2 in the Data Modeler (which is part of SQL Developer), and you can compare models, but the generation of DDL synch scripts is reserved for Oracle data models only.

OLE DB provider for ADO.NET data source

I have an application which can connect to OLE DB data sources, however, my proprietary database has only ADO.NET provider.
Is there any ADO.NET to OLE DB bridge which could helps me to connect to ADO.NET data source?
EDIT:
I do not have control on application. It is some kind of reporting service. Here is how I expect to connect:
App <-> OLE DB Provider <-> (bridge?) <-> ADO.NET Data Source
Everything is running on Windows machine
You didn't mention the platform so I am going to assume things and point you to some direction.
For the .NET Framework Data Provider for OLE DB, the connection string
format is identical to the connection string format used in ADO
For more details you can refer to this page to get started:
Connecting to an OLE DB Data Source Using ADO.NET
And also it wouldn't hurt to have a look at this title Connecting to an OLE DB Data Source
in the following MSDN article (.NET 4.5)
Establishing the Connection
Update
On the other hand to access a ADO.NET data source using an OLE DB you can follow this example.
However if you mean by the word "bridge" to have something like
using (SqlConnection connection = new SqlConnection(oleConnectionString))
where, oleConnectionString is an originally an OLE connection string which is converted to act as an SQL connection string?! I am not sure if that's possible.
ADO.NET Sample

Can firebird database connect to other databases using like linked server in SQL Server?

I know that SQL Server has linked server that allow it to connect to other database and execute query. Now I am using firebird. I wonder if firebird has its "linked server" to access other databases. Thanks!
Firebird doesn't have a linked server feature. There is a limited method for accessing other Firebird databases (either remote or locally) using EXECUTE STATEMENT, however this only supports Firebird database, and you need to provide the data source information on each invocation.

How to connect to particular database in Oracle 10g

Suppose I have multiple Oracle databases in the same server. Now I want to connect to particular database and query a table just like SQL Server 2008. How to start particular Oracle database?
If you are using SQL*Plus, the most common syntax for opening a connection is
sqlplus user_name/password#tns_alias
In this example TNS_ALIAS is the TNS alias for the particular database you want to connect to (most likely "XE" based on your followups to inium's answer). If you want to connect to a different database, you would need to specify a TNS alias for that specific database.
Note that since you are coming from a SQL Server background, the SQL Server definition of a database is rather different than the Oracle definition. What SQL Server calls a database is similar logically to what Oracle calls a schema (and similar physically to what Oracle calls a tablespace). So when you're dealing with Oracle, it's much more common to have many schemas in a single database than to have a large number of databases on a server. This is particularly true if you're using the Express Edition (Oracle XE) where you're generally limited to one database per machine.
go to cmd and type sqlplus <database-name>/<database-password>
You can use SQL Developer, it's similar to SQL Enterprise Manager 2005. Just create a new connection using the db user name and password.