CTBCAFDb - Revision history

Abrassard: /* Initializing CTBCAFDb */

2011-05-30T18:55:30Z

Initializing CTBCAFDb

Abrassard: /* Example code */

2011-05-30T18:50:44Z

Example code

Abrassard: First version of this doc

2011-05-30T16:09:28Z

First version of this doc

New page

This class is used to connect to a MySql database.

The CAF library contains DAOs (Database Access Objects) for each table found in the Toolpack configuration database. These DAOs include a class to retrieve the table rows, and a class that represents the content of one database row.

To initialize the DAOs, it's mandatory that the application uses the class ''CTBCAFDb'' to access the MySql database.

For more information on using the DAOs, please refer to the following page: [[Accessing_Toolpack_DB]]

== Initializing ''CTBCAFDb'' ==
The constructor of ''CTBCAFDb'' (as well as function ''SetConnectString'') receive a "connection string" as an argument.
This connection string is of the form:
ODBC:SERVER=10.3.2.240/10.3.6.240;PORT=3306;UID=root;PWD=root;DATABASE=toolpack_0

The application should use the connection string provided by Toolpack OAM system through class CTBCAFServiceCmMgmtClient (see [[CTBCAFServiceCmMgmtClient:]] for more information).

== Connecting to the database ==
To connect to the database using the previously provided connection string, use the ''Open'' function.

== Querying the database ==
To query the database:
* Create a new query using function ''CreateQuery''
* Use the query object's ''Exec'' function to start the query
* Get query result using functions ''NextRow'', ''ColCount'', ''ColName'', and ''ColValue'', etc.
* Delete the query object

'''Warning''': Opening the database and executing queries are synchronous operations, and will block if the database is not available. It is thus recommended to call that function using a background thread in the application that will not prevent the application from properly running while the database is attempted to be accessed. Among other things, the application shall continue to respond to Toolpack OAM Heart-beat (see [[CTBCAFServiceAlmMgmt]]) even while waiting for database operation to complete, to avoid the application from being killed during that time.

== Example code ==

← Older revision		Revision as of 18:50, 30 May 2011
Line 27:		Line 27:

	== Example code ==		== Example code ==
		+	Here is some example code that show how to perform a simple query.
		+
		+	Pre-requisites for the code below:
		+	* The application must have initialized an object of class ''CTBCAFServiceCmMgmtClient''
		+	* The application must have received the callback ''OnReloadConfig'' inherited from ''ITBCAFServiceCmMgmtClient''
		+	* The application must have connected to the database:
		+	** using an object of type ''CTBCAFDb'' (''mpConfigDb'' in the example code below)
		+	** connected to the DB using the connection string received by ''OnReloadConfig''
		+	* The application must use the "configuration id" as received by ''OnReloadConfig'' (''mun32ConfigurationId'' in the example code below)
		+
		+	TBX_RESULT MyApplication::ExampleDbQuery()
		+	{
		+	TBX_RESULT Result;
		+	CTBCAFString strQuery;
		+	PITBCAFDbQuery pQuery = NULL;
		+
		+	/*---------------------------------------------------------------------------------------------------------------------------
		+	\| Code section
		+	--------------------------------------------------------------------------------------------------------------------------/
		+	CAFCODE( MyApplication::ExampleDbQuery )
		+	{
		+	// Build the SQL query string that we want to perform
		+	strQuery.Format
		+	(
		+	"select * from virtual_adapters where configuration_id = %u",
		+	mun32ConfigurationId
		+	);
		+	pQuery = mpConfigDb->CreateQuery( strQuery );
		+	TBCAF_EXIT_ON_NULL( pQuery, TBX_RESULT_FAIL, "Failed to query query object" );
		+
		+	// Execute the query
		+	Result = pQuery->Exec( mpConfigDb );
		+	TBCAF_EXIT_ON_ERROR( Result, "Failed to execute query" );
		+
		+	// Collect the results for each returned row
		+	while( pQuery->NextRow() )
		+	{
		+	// Get and print value of column "name"
		+	CTBCAFVariant Value = pQuery->ColValue( "name" );
		+	LogTrace( TBCAF_TRACE_LEVEL_ALWAYS, FMAGEN "Found adapter %s\n", Value.ToString().c_str() );
		+	}
		+
		+	TBX_EXIT_SUCCESS( TBX_RESULT_OK );
		+	}
		+
		+	/*---------------------------------------------------------------------------------------------------------------------------
		+	\| Exception handling section
		+	--------------------------------------------------------------------------------------------------------------------------/
		+	CAF_EXCEPTION_HANDLING
		+
		+	/*---------------------------------------------------------------------------------------------------------------------------
		+	\| Error handling section
		+	--------------------------------------------------------------------------------------------------------------------------/
		+	CAF_ERROR_HANDLING( CAF_VERBOSE )
		+	{
		+	}
		+
		+	/*---------------------------------------------------------------------------------------------------------------------------
		+	\| Cleanup section
		+	--------------------------------------------------------------------------------------------------------------------------/
		+	CAF_CLEANUP
		+	{
		+	delete pQuery;
		+	pQuery = NULL;
		+	}
		+
		+	RETURN;
		+	}

@@ Line 12: / Line 12: @@
   ODBC:SERVER=10.3.2.240/10.3.6.240;PORT=3306;UID=root;PWD=root;DATABASE=toolpack_0
-The application should use the connection string provided by Toolpack OAM system through class CTBCAFServiceCmMgmtClient (see [[CTBCAFServiceCmMgmtClient:]] for more information).
+The application should use the connection string provided by Toolpack OAM system through class CTBCAFServiceCmMgmtClient (see [[CTBCAFServiceCmMgmtClient]] for more information).
 == Connecting to the database ==