Use Mongo in C ++ to perform count and distinct operations

Assume that the server has the Mongo database MyDB, including the MyTable table and the fields "IP" and "Date", which respectively record the Client IP address and access time for accessing the service, account User with access permission to the MyTable table, password 123456
 
(1) create a connection
 
 
Mongo: DBClientConnection pConn = new mongo: DBClientConnection;
String strErr;
PConn-> connect ("127.0.0.1", strErr)
PConn-> auth ("MyDB", "User", "123456", strErr );
 
 
(2) count operation
// Count the number of records of the specified date in the range DateStart and DateEnd
// "$ Gte" is a comparison operator of Mongo >=, "$ lte" is <=, "$ gt" is>, and "$ lt" is <
 
 
Int64 DateStart = 1315014772, DateEnd = 1317606772;
Unsigned int64 u64Count = pConn-> count ("MyTable ",
BSON ("Date" <BSON ("$ gte" <DateStart <"$ lte" <DateEnd )));
 
 
(3) distinct operation
// Number of all different IP addresses in the statistical table
 
 
Bo bobj;
PConn-> runCommand ("MyDB ",
BSON ("distinct" <"MyTabel" <"key" <"IP", bobj ));
Vector <be> vecbe = obj. getField ("values"). Array ();
Size_t szIPCount = vecbe. size ();
 
// View the specific IP Address
Vector <string> vecIP;
For (size_t I = 0; I <szIPCount; I ++)
{
VecIP. push_back (vecbe [I]. String ());
}
 
// The number of different client IP addresses that access the service in a certain period of time according to the condition statistics
 
 
PConn-> runCommand ("MyDB ",
BSON ("distinct" <"MyTabel" <"key" <"IP"
<"Query" <BSON ("Date" <BSON ("$ gte" <DateStart <"$ lte" <DateEnd), obj );
 

From the shellching Column