[Ilusion9]

Database hDatabase = null;
 
public void OnPluginStart()
{
	Database.Connect(GotDatabase, "sqltest");
}
 
public void GotDatabase(Database db, const char[] error, any data)
{
	if (db == null)
	{
		LogError("Database failure: %s", error);
	} 
        else 
        {
		hDatabase = db;
	}
}

or

Database hDatabase = null;
 
public void OnMapStart()
{
	if (hDatabase == null)
	{
		Database.Connect(GotDatabase, "sqltest");
	}
}
 
public void GotDatabase(Database db, const char[] error, any data)
{
	if (db == null)
	{
		LogError("Database failure: %s", error);
	} 
        else 
        {
		hDatabase = db;
	}
}