Open Database Connectivity (ODBC) is a database access interface standard based on the Windows environment. It was developed to solve the problem of data sharing among heterogeneous databases. It has now become a major part of WOSA (The Windows Open System Architecture).
ODBC provides a unified interface for accessing heterogeneous databases. It allows applications to access data managed by different database management systems (DBMSs) using SQL as the data access standard. It enables applications to manipulate data directly in the database, eliminating the need for changes when the database changes. ODBC allows access to database files on various computers and also to non-database objects such as Excel sheets and ASCII data files.
OceanBase Connector/ODBC is customized based on the MySQL ODBC driver. It allows for using the new data models provided by OceanBase Database, such as array. The following figure shows the architecture of OceanBase Connector/ODBC.
Application
An application accesses data on an OBServer using the standard ODBC API. The ODBC API then communicates with the driver manager. To access data, the application only needs to know the data source name (DSN) and does not need to know where the data is stored, how it is stored, or how the system is configured.
The following tasks are common to all applications that use ODBC:
- Selecting and connecting to OBServer
- Submitting SQL statements for execution
- Retrieving results (if any)
- Handling errors
- Committing or rolling back transactions that contain SQL statements
- Disconnecting from OBServer
Since most data access work is done using SQL, the main task of applications that use OceanBase Connector/ODBC is to submit SQL statements and retrieve the results generated by these statements.
Driver manager
The driver manager is a library used to manage communication between an application and a driver. It mainly performs the following tasks:
- Parsing the DSN used to connect to the database. Database connection information is identified by the DSN. The DSN is a configuration string that identifies the database driver, database, database host, and optional authentication information. Any ODBC-compatible application can use the pre-configured, identical DSN to connect to the data source.
- Loading and unloading the driver required to access the database defined in the DSN. For example, if you configure a DSN to connect to an OceanBase database, the driver manager will load the OceanBase Connector/ODBC driver so that the ODBC API can communicate with the OBServer.
- Handling ODBC function calls or passing them to the driver.
OceanBase Connector/ODBC
OceanBase Connector/ODBC is a library used to implement the functions supported by the ODBC API. It is used to handle ODBC function calls, submit SQL requests to the OBServer, and return the results to the application. It allows for modifying application requests as needed to comply with the syntax rules of OceanBase Database.
ODBC.INI
The ODBC.INI configuration file stores the driver and database information required to connect to the OBServer. According to the DSN defined in ODBC.INI, the driver manager can determine the driver to load, and the driver can read the connection parameters.
OBServer
OBServer stores information for the OceanBase database. Query operations retrieve data from the database, while insert and update operations modify data in the database.