Development Based on ODBC

ODBC is a Microsoft API for accessing databases based on the X/OPEN CLI. ODBC APIs alleviate applications from directly operating in databases, and enhance the database portability, extensibility, and maintainability.

Figure 1 shows the system structure of ODBC.

Figure 1 ODBC system structure
Click to enlarge

GaussDB supports ODBC 3.5 in the following environments.

**Table 1** OSs Supported by ODBC
OS	Platform
EulerOS 2.5	x86_64
EulerOS 2.8	Arm64
Windows 7	x86_32
Windows 7	x86_64
Windows Server 2008	x86_32
Windows Server 2008	x86_64
Kylin V10	x86_64
Kylin V10	Arm64

The ODBC Driver Manager running on Unix or Linux can be unixODBC or iODBC. unixODBC-2.3.0 is used as the component for connecting to the database.

Windows has a native ODBC Driver Manager. You can locate Data Sources (ODBC) by choosing Control Panel > Administrative Tools.

The current database ODBC driver is based on an open-source version and may be incompatible with Huawei-developed data types such as tinyint, smalldatetime, and nvarchar2.

ODBC Constraints

ODBC does not support user-defined types and does not support user-defined parameters in stored procedures.
ODBC does not support DR switchover.
When the proc_outparam_override parameter is enabled for the database, ODBC cannot properly call the stored procedure that contains the out parameter.