SQLAllocEnv Mapping

SQLAllocEnv Mapping


When an application calls SQLAllocEnv through an ODBC 3.x driver, the call to SQLAllocEnv(phenv) is mapped to SQLAllocHandle as follows:

  1. The Driver Manager allocates an environment handle and returns it to the application. The Driver Manager calls SQLSetEnvAttr to set the SQL_ATTR_ODBC_VERSION environment attribute to SQL_OV_ODBC2.

  2. When the application establishes the first connection to a driver, the Driver Manager calls

    SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, OutputHandlePtr)

    in the driver with OutputHandlePtr set to phenv.

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