odbcpp: odbcpp::handle Class Reference

Initialize the low level handle.

This function initialize the handle as expected.

At the start, the handle pointer is set to NULL. The super class must define that handle in its constructor.

Definition at line 131 of file handle.cpp.

Clean up the handle.

This function will free the handle as expected.

If it is necessary to have a function called before the handle can be freed, it needs to be done in the desctructor of the specific handle.

For instance, the connection handle needs to get disconnected first.

Definition at line 150 of file handle.cpp.

References f_handle, and f_handle_type.

Cannot copy handles, really, won't work!

Definition at line 51 of file handle.h.

Check the return code of an SQL function call.

This function checks the return code of an SQL function called on this handle. If the return code represents an error, then an odbcpp_error is thrown.

In all cases, a diagnostic is generated.

The following is how this function is usually used:

        check(SQLExecDirect( ... ));

And yes, that means most of the necessary error handling is done in this function.

If the function may return a code that needs special handling such as SQL_NO_DATA returned by SQLFetch(), then you should test the code before calling the check() function.

Parameters:

[in]	return_code	The code returned by an SQL function
[in]	parent	The parent handle when allocating a child handle

Returns:

A copy of the return_code parameter

Definition at line 184 of file handle.cpp.

References f_diag, f_handle, and f_handle_type.

Referenced by odbcpp::statement::cancel(), odbcpp::statement::close_cursor(), odbcpp::statement::cols(), odbcpp::environment::commit(), odbcpp::connection::commit(), odbcpp::connection::connect(), odbcpp::connection::connection(), odbcpp::connection::disconnect(), odbcpp::environment::environment(), odbcpp::statement::execute(), odbcpp::statement::fetch(), odbcpp::environment::get_data_source(), odbcpp::environment::rollback(), odbcpp::connection::rollback(), odbcpp::statement::rows(), odbcpp::statement::set_attr(), odbcpp::environment::set_attr(), odbcpp::connection::set_attr(), and odbcpp::statement::statement().

Get a reference to the current diagnostic of this handle.

Each time an ODBC function is called, a diagnostic is generated. Some of these diagnostics are saved in the handle diagnostic variable member that can be retrieved using this function.

The diagnostics hold information such as the last error or warning and the number of rows affected by the last executed SQL statement.

Returns:

A reference to the handle diagnostic.

Definition at line 43 of file handle.h.

References f_diag.

Retrieve the SQL handle.

This function lets you retrieve the SQL handle.

Bug:

Be careful, by getting and using the SQL handle directly you may change the internal state without the odbcpp library knowing and thus later have it generate unexpected errors.

Returns:

The SQL handle

Definition at line 41 of file handle.h.

References f_handle.

Referenced by odbcpp::diagnostic::diagnostic().

Retrieve the type of handle.

This function returns the type of handle as specified at the time the handle is constructed (it cannot be changed at a later time.)

The returned value is the untranslated ODBC type.

Returns:

The ODBC type of this handle.

Definition at line 42 of file handle.h.

References f_handle_type.

Referenced by odbcpp::diagnostic::diagnostic().

Cannot copy handles, really, won't work!

Definition at line 53 of file handle.h.

The last command diagnostics.

Whenever a command is called, its diagnostics are saved in this variable.

A reference to the diagnostics can be retrieved using the handle::get_diagnostic() function.

A diagnostic is accessible in an exception when one is generated.

Definition at line 55 of file handle.h.

Referenced by check(), and get_diagnostic().

The ODBC handle.

This variable member is the ODBC handle to be used with the different SQL functions. This is a bare pointer.

The handle will be freed at the time the handle is deleted. It should not be freed by hand in any other way.

For faster access, the handle is protected instead of private.

Definition at line 46 of file handle.h.

Referenced by odbcpp::statement::cancel(), check(), odbcpp::statement::close_cursor(), odbcpp::statement::cols(), odbcpp::environment::commit(), odbcpp::connection::commit(), odbcpp::connection::connect(), odbcpp::connection::connection(), odbcpp::connection::disconnect(), odbcpp::environment::environment(), odbcpp::statement::execute(), odbcpp::statement::fetch(), odbcpp::environment::get_data_source(), get_handle(), odbcpp::environment::rollback(), odbcpp::connection::rollback(), odbcpp::statement::rows(), odbcpp::statement::set_attr(), odbcpp::environment::set_attr(), odbcpp::connection::set_attr(), odbcpp::statement::statement(), and ~handle().

The type of the ODBC handle.

This variable member holds the type of the handle.

Notice that it is defined at construction time and it is read-only and thus it cannot be changed (in effect, it is hard coded.)

This is the type as defined in the ODBC header files.

Definition at line 47 of file handle.h.

Referenced by check(), odbcpp::environment::commit(), odbcpp::connection::commit(), odbcpp::connection::connection(), odbcpp::environment::environment(), get_handle_type(), odbcpp::environment::rollback(), odbcpp::connection::rollback(), odbcpp::statement::statement(), and ~handle().