/// \file
/// \ingroup tutorial_sql
/// \notebook -js
///
/// 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/download/root_download_stats.sqlite
/// In order to demonstrate the dependency over ROOT version 6.14, this tutorial uses the TSQLResult
/// function which allows to extract the minimum time stored in the SQlite3 database.
/// The next step is to create a TH1F Histogram, which will be filled with the values stored in
/// two different columns from the database, the "Time" and "Version" columns.
/// This product includes GeoLite2 data created by MaxMind, available from
/// http://www.maxmind.com.
///
/// \macro_code
///
/// \author Alexandra-Maria Dobrescu 08/2018
#include
#include
#include
#include
void SQLiteTimeVersionOfRoot(){
TSQLServer *db = TSQLServer::Connect("sqlite://root_download_stats.sqlite", "", "");
const char *minTime = "SELECT min(Time) FROM accesslog;";
TSQLResult *minTimeRes = db->Query(minTime);
std::string strMinTimeField = minTimeRes->Next()->GetField(0);
TDatime minTimeFormat(strMinTimeField.c_str());
TDatime now;
TH1F *hTime = new TH1F("hTime", "Duration of ROOT dependency over version 6.14", 10, minTimeFormat.Convert(), now.Convert());
const char *time = "SELECT Time, Version FROM accesslog;";
TSQLResult *timeRes = db->Query(time);
while (TSQLRow *row = timeRes->Next()) {
TDatime rowTime(row->GetField(0));
TString rowVersion(row->GetField(1));
TString shortVersion(rowVersion(0,4));
if ( shortVersion == "6.14" ) {
hTime->Fill(rowTime.Convert());
}
delete row;
}
TCanvas *timeHistogram = new TCanvas();
gStyle->SetTimeOffset(0);
hTime->GetXaxis()->SetTimeDisplay(1);
hTime->GetXaxis()->SetLabelSize(0.02);
hTime->GetXaxis()->SetNdivisions(512, kFALSE);
hTime->GetXaxis()->SetTimeFormat("%Y-%m-%d");
hTime->Draw();
}