According to Microsoft, ODBC is a specification for a database API.  This API is database and operating system agnostic due to the fact that the primary goal of the ODBC API is to be language-independent. Additionally, the open functions of the API are created by the manufactures of DBMS-specific drivers. Developers can use these exposed functions from within their own custom applications so that they can communicate with DBMS through the language-independent drivers.

ODBC Advantages

• Multiple ODBC drivers for each DBSM

  • Example

    • Oracle’s ODBC Driver

    • Merant’s Oracle Driver
    • Microsoft’s Oracle Driver
• ODBC Drivers are constantly updated for the latest data types
• ODBC allows for more control when querying
• ODBC allows for Isolation Levels

ODBC Disadvantages

• ODBC Requires DSN
• ODBC is the proxy between an application and a database
• ODBC is dependent on third party drivers

ODBC Transaction Isolation Levels are related to and limited by the transaction management capabilities of the data source.

Transaction isolation levels:

•  READ UNCOMMITTED

  • Data is allowed to be read prior to the committing of a transaction.

•  READ COMMITTED

  • Data is only accessible after a transaction has completed

•  REPEATABLE READ

  • The same data value is read during the entire transaction

•  SERIALIZABLE

  • Transactions have no effect on other transactions