Pretty much every
application deals with data in some manner, whether that data comes from
memory, databases, XML files, text files, or something else. The location where
we store the data can be called as a Data Source or Data Store where a Data Source
can be a file, database, or indexing server etc.
Programming
Languages cannot communicate with Data Sources directly because each Data
Source adopts a different Protocol (set of rules) for communication, so to
overcome this problem long back Microsoft has introduced intermediate technologies
like JET, Odbc and Oledb which works like bridge between the Applications and
Data Sources to communicate with each other.
The
Microsoft Jet Database Engine is a database engine on which several Microsoft
products have been built. A database engine is the underlying component of a
database, a collection of information stored on a computer in a systematic way.
The first version of Jet was developed in 1992, consisting of three modules
which could be used to manipulate a database. JET stands for Joint Engine
Technology, sometimes being referred to as Microsoft JET Engine or simply Jet.
Microsoft Access and Excel uses Jet as their underlying database engine. Over
the years, Jet has become almost synonymous with Microsoft Access, to the
extent where many people refer to a Jet database as an "Access
database". MS developed Jet database system, a C-based interface allowing
applications to access that data, and a selection of driver DLLs that allowed
the same C interface to redirect input and output to databases. However, Jet
did not use SQL; the interface was in C and consisted of data structures and
function calls.
ODBC
(Open Database Connectivity) is a standard C programming language middleware
API for accessing database management systems (DBMS). ODBC accomplishes DBMS
independence by using an ODBC driver as a translation layer between the
application and the DBMS. The application uses ODBC functions through an ODBC
driver manager with which it is linked, and the driver passes the query to the
DBMS. An ODBC driver will be providing a standard set of functions for the
application to use, and implementing DBMS-specific functionality. An
application that can use ODBC is referred to as "ODBC-compliant". Any
ODBC-compliant application can access any DBMS for which a driver is installed.
Drivers exist for all major DBMSs as well as for many other data sources like
Microsoft Excel, and even for text or CSV files. ODBC was originally developed
by Microsoft during the early 1990s.
OLE
DB (Object Linking and Embedding, Database, sometimes written as OLEDB or
OLE-DB), an API designed by Microsoft, allows accessing data from a variety of
sources in a uniform manner. The API provides a set of interfaces implemented
using the Component Object Model (COM). Microsoft originally intended OLE DB as
a higher-level replacement for, and successor to, ODBC, extending its feature
set to support a wider variety of non-relational databases, such as object
databases and spreadsheets that do not necessarily implement SQL. OLE DB is
conceptually divided into consumers and providers. The consumers are the
applications that need access to the data, and the providers are the software
components that implement the interface and thereby provide the data to the
consumer. An OLE DB provider is a software component enabling an OLE DB
consumer to interact with a data source. OLE DB providers are alike to ODBC
drivers or JDBC drivers for Java. OLE DB providers can be created to access
such simple data stores as a text file and spreadsheet, through to such complex
databases as Oracle, Microsoft SQL Server, and many others. It can also provide
access to hierarchical data stores.
0 comments:
Post a Comment