This tutorial demonstrates how TSQLServer can be used to create a connection with a SQlite3 database. It accesses the Sqlite data base. Download from https://root.cern/files/root_download_stats.sqlite The world map is hold by a TH2Poly histogram which, after filling, will show the world wide dispersion of ROOT's users. To histogram filling, is done having as input parameters the two columns of the database: "IPLongitude' - for the longitude, and the "IPLatitude" - for the latitude. The data related to the latitude and the longitude has been provided from the log files storing the users IP. This product includes GeoLite2 data created by MaxMind, available from http://www.maxmind.com.

Author: Alexandra-Maria Dobrescu 08/2018
This notebook tutorial was automatically generated with ROOTBOOK-izer from the macro found in the ROOT repository on Sunday, October 02, 2022 at 09:38 AM.

In [ ]:
TSQLServer *db = TSQLServer::Connect("sqlite://root_download_stats.sqlite", "", "");

TFile *F = TFile::Open("http://root.cern.ch/files/WM.root");
TH2Poly *WM;
WM = (TH2Poly*) F->Get("WM");
const char *location = "SELECT IPLatitude, IPLongitude FROM accesslog;";
TSQLResult *locationRes = db->Query(location);

while (TSQLRow *row = locationRes->Next()) {
   if (!row->GetField(0)[0])
   std::string sLatitude(row->GetField(0));
   std::string sLongitude(row->GetField(1));
   float latitude = std::stof(sLatitude);
   float longitude = std::stof(sLongitude);
   WM->Fill(longitude, latitude);

  delete row;

TCanvas *locationHistogram = new TCanvas();


Draw all canvases

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%jsroot on