I have 2 databases with 1 collection and the same documents, this databases run in localhost. The documents in the different databases differ only in their structure.
Example of Structure 1
{"_id":{"$oid":"5f8ffa19a46b9d4179eaf943"},"Nome":"Eduino Dykstra","Data nascita":"March 4, 1980","Nazionalità":"Togo","Ruolo":"FW","Link calciatore":"https://fbref.com/en/players/vjLRENdD/Eduino-Dykstra","Stagioni":[{"season":"2006-2007","age":{"$numberInt":"27"},"squad":"Atlas","country":"mx MEX","comp_level":"1. Liga MX","lg_finish":"18th","games":{"$numberInt":"2"},"games_starts":{"$numberInt":"0"},"minutes":{"$numberInt":"32"},"goals":{"$numberInt":"0"},"assists":{"$numberInt":"0"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"0"},"cards_yellow":{"$numberInt":"0"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"0"},"assists_per90":{"$numberDouble":"0"},"goals_assists_per90":{"$numberDouble":"0"},"goals_pens_per90":{"$numberDouble":"0"},"goals_assists_pens_per90":{"$numberDouble":"0"},"xg":{"$numberDouble":"0.52"},"npxg":{"$numberDouble":"0.52"},"xa":{"$numberDouble":"0.58"},"xg_per90":{"$numberDouble":"0"},"xa_per90":{"$numberDouble":"0"},"xg_xa_per90":{"$numberDouble":"0"},"npxg_per90":{"$numberDouble":"0"},"npxg_xa_per90":{"$numberDouble":"0"}},{"season":"2007-2008","age":{"$numberInt":"28"},"squad":"Puebla","country":"mx MEX","comp_level":"1. Liga MX","lg_finish":"8th","games":{"$numberInt":"0"},"games_starts":{"$numberInt":"0"},"minutes":{"$numberInt":"0"},"goals":{"$numberInt":"0"},"assists":{"$numberInt":"0"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"0"},"cards_yellow":{"$numberInt":"0"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"0"},"assists_per90":{"$numberDouble":"0"},"goals_assists_per90":{"$numberDouble":"0"},"goals_pens_per90":{"$numberDouble":"0"},"goals_assists_pens_per90":{"$numberDouble":"0"},"xg":{"$numberDouble":"0"},"npxg":{"$numberDouble":"0"},"xa":{"$numberDouble":"0.81"},"xg_per90":{"$numberDouble":"0"},"xa_per90":{"$numberDouble":"0"},"xg_xa_per90":{"$numberDouble":"0"},"npxg_per90":{"$numberDouble":"0"},"npxg_xa_per90":{"$numberDouble":"0"}},{"season":"2008-2009","age":{"$numberInt":"29"},"squad":"Villarreal","country":"es ESP","comp_level":"1. La Liga","lg_finish":"5th","games":{"$numberInt":"3"},"games_starts":{"$numberInt":"0"},"minutes":{"$numberInt":"98"},"goals":{"$numberInt":"0"},"assists":{"$numberInt":"0"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"0"},"cards_yellow":{"$numberInt":"0"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"0"},"assists_per90":{"$numberDouble":"0"},"goals_assists_per90":{"$numberDouble":"0"},"goals_pens_per90":{"$numberDouble":"0"},"goals_assists_pens_per90":{"$numberDouble":"0"},"xg":{"$numberDouble":"0.08"},"npxg":{"$numberDouble":"0.08"},"xa":{"$numberDouble":"0.97"},"xg_per90":{"$numberDouble":"0.08"},"xa_per90":{"$numberDouble":"0.97"},"xg_xa_per90":{"$numberDouble":"1.05"},"npxg_per90":{"$numberDouble":"0.08"},"npxg_xa_per90":{"$numberDouble":"1.05"}},{"season":"2009-2010","age":{"$numberInt":"30"},"squad":"Nantes","country":"fr FRA","comp_level":"1. Ligue 1","lg_finish":"13th","games":{"$numberInt":"21"},"games_starts":{"$numberInt":"20"},"minutes":{"$numberInt":"1040"},"goals":{"$numberInt":"13"},"assists":{"$numberInt":"2"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"1"},"cards_yellow":{"$numberInt":"0"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"1.18"},"assists_per90":{"$numberDouble":"0.18"},"goals_assists_per90":{"$numberDouble":"1.35"},"goals_pens_per90":{"$numberDouble":"1.18"},"goals_assists_pens_per90":{"$numberDouble":"1.36"},"xg":{"$numberDouble":"10.4"},"npxg":{"$numberDouble":"10.4"},"xa":{"$numberDouble":"0.72"},"xg_per90":{"$numberDouble":"0.94"},"xa_per90":{"$numberDouble":"0.06"},"xg_xa_per90":{"$numberDouble":"1"},"npxg_per90":{"$numberDouble":"0.94"},"npxg_xa_per90":{"$numberDouble":"1"}},{"season":"2010-2011","age":{"$numberInt":"31"},"squad":"FC Khimki","country":"ru RUS","comp_level":"1. Russian Premier League","lg_finish":"15th","games":{"$numberInt":"27"},"games_starts":{"$numberInt":"2"},"minutes":{"$numberInt":"570"},"goals":{"$numberInt":"10"},"assists":{"$numberInt":"1"},"pens_made":{"$numberInt":"1"},"pens_att":{"$numberInt":"2"},"cards_yellow":{"$numberInt":"1"},"cards_red":{"$numberInt":"1"},"goals_per90":{"$numberDouble":"1.66"},"assists_per90":{"$numberDouble":"0.16"},"goals_assists_per90":{"$numberDouble":"1.81"},"goals_pens_per90":{"$numberDouble":"1.5"},"goals_assists_pens_per90":{"$numberDouble":"1.66"},"xg":{"$numberDouble":"9.41"},"npxg":{"$numberDouble":"7.37"},"xa":{"$numberDouble":"0.91"},"xg_per90":{"$numberDouble":"1.56"},"xa_per90":{"$numberDouble":"0.15"},"xg_xa_per90":{"$numberDouble":"1.71"},"npxg_per90":{"$numberDouble":"1.22"},"npxg_xa_per90":{"$numberDouble":"1.36"}},{"season":"2011-2012","age":{"$numberInt":"32"},"squad":"Cagliari","country":"it ITA","comp_level":"1. Serie A","lg_finish":"14th","games":{"$numberInt":"6"},"games_starts":{"$numberInt":"0"},"minutes":{"$numberInt":"186"},"goals":{"$numberInt":"1"},"assists":{"$numberInt":"0"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"0"},"cards_yellow":{"$numberInt":"0"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"0.5"},"assists_per90":{"$numberDouble":"0"},"goals_assists_per90":{"$numberDouble":"0.5"},"goals_pens_per90":{"$numberDouble":"0.5"},"goals_assists_pens_per90":{"$numberDouble":"0.5"},"xg":{"$numberDouble":"0.43"},"npxg":{"$numberDouble":"0.43"},"xa":{"$numberDouble":"0.54"},"xg_per90":{"$numberDouble":"0.21"},"xa_per90":{"$numberDouble":"0.27"},"xg_xa_per90":{"$numberDouble":"0.48"},"npxg_per90":{"$numberDouble":"0.21"},"npxg_xa_per90":{"$numberDouble":"0.48"}},{"season":"2012-2013","age":{"$numberInt":"33"},"squad":"Defensa y Just","country":"ar ARG","comp_level":"1. Primera Div","lg_finish":"6th","games":{"$numberInt":"5"},"games_starts":{"$numberInt":"2"},"minutes":{"$numberInt":"220"},"goals":{"$numberInt":"3"},"assists":{"$numberInt":"0"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"0"},"cards_yellow":{"$numberInt":"0"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"1.5"},"assists_per90":{"$numberDouble":"0"},"goals_assists_per90":{"$numberDouble":"1.5"},"goals_pens_per90":{"$numberDouble":"1.5"},"goals_assists_pens_per90":{"$numberDouble":"1.5"},"xg":{"$numberDouble":"1.53"},"npxg":{"$numberDouble":"1.53"},"xa":{"$numberDouble":"0.38"},"xg_per90":{"$numberDouble":"0.76"},"xa_per90":{"$numberDouble":"0.19"},"xg_xa_per90":{"$numberDouble":"0.95"},"npxg_per90":{"$numberDouble":"0.76"},"npxg_xa_per90":{"$numberDouble":"0.95"}},{"season":"2013-2014","age":{"$numberInt":"34"},"squad":"Emmen","country":"nl NED","comp_level":"1. Dutch Eredivisie","lg_finish":"12th","games":{"$numberInt":"14"},"games_starts":{"$numberInt":"12"},"minutes":{"$numberInt":"963"},"goals":{"$numberInt":"5"},"assists":{"$numberInt":"1"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"0"},"cards_yellow":{"$numberInt":"1"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"0.5"},"assists_per90":{"$numberDouble":"0.1"},"goals_assists_per90":{"$numberDouble":"0.6"},"goals_pens_per90":{"$numberDouble":"0.5"},"goals_assists_pens_per90":{"$numberDouble":"0.6"},"xg":{"$numberDouble":"5.32"},"npxg":{"$numberDouble":"5.32"},"xa":{"$numberDouble":"1.09"},"xg_per90":{"$numberDouble":"0.53"},"xa_per90":{"$numberDouble":"0.1"},"xg_xa_per90":{"$numberDouble":"0.63"},"npxg_per90":{"$numberDouble":"0.53"},"npxg_xa_per90":{"$numberDouble":"0.63"}},{"season":"2014-2015","age":{"$numberInt":"35"},"squad":"Munchen Gladbach","country":"de GER","comp_level":"1. Bundesliga","lg_finish":"4th","games":{"$numberInt":"33"},"games_starts":{"$numberInt":"6"},"minutes":{"$numberInt":"967"},"goals":{"$numberInt":"18"},"assists":{"$numberInt":"3"},"pens_made":{"$numberInt":"4"},"pens_att":{"$numberInt":"6"},"cards_yellow":{"$numberInt":"0"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"1.8"},"assists_per90":{"$numberDouble":"0.3"},"goals_assists_per90":{"$numberDouble":"2.1"},"goals_pens_per90":{"$numberDouble":"1.4"},"goals_assists_pens_per90":{"$numberDouble":"1.7"},"xg":{"$numberDouble":"16.2"},"npxg":{"$numberDouble":"13"},"xa":{"$numberDouble":"2.54"},"xg_per90":{"$numberDouble":"1.61"},"xa_per90":{"$numberDouble":"0.25"},"xg_xa_per90":{"$numberDouble":"1.86"},"npxg_per90":{"$numberDouble":"1.3"},"npxg_xa_per90":{"$numberDouble":"1.55"}},{"season":"2015-2016","age":{"$numberInt":"36"},"squad":"Schalke 04","country":"de GER","comp_level":"1. Bundesliga","lg_finish":"12th","games":{"$numberInt":"22"},"games_starts":{"$numberInt":"0"},"minutes":{"$numberInt":"667"},"goals":{"$numberInt":"6"},"assists":{"$numberInt":"3"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"1"},"cards_yellow":{"$numberInt":"1"},"cards_red":{"$numberInt":"1"},"goals_per90":{"$numberDouble":"0.85"},"assists_per90":{"$numberDouble":"0.42"},"goals_assists_per90":{"$numberDouble":"1.27"},"goals_pens_per90":{"$numberDouble":"0.85"},"goals_assists_pens_per90":{"$numberDouble":"1.28"},"xg":{"$numberDouble":"1.26"},"npxg":{"$numberDouble":"1.26"},"xa":{"$numberDouble":"1.71"},"xg_per90":{"$numberDouble":"0.18"},"xa_per90":{"$numberDouble":"0.24"},"xg_xa_per90":{"$numberDouble":"0.42"},"npxg_per90":{"$numberDouble":"0.18"},"npxg_xa_per90":{"$numberDouble":"0.42"}},{"season":"2016-2017","age":{"$numberInt":"37"},"squad":"Sheffield Utd","country":"eng ENG","comp_level":"1. Premier League","lg_finish":"9th","games":{"$numberInt":"5"},"games_starts":{"$numberInt":"3"},"minutes":{"$numberInt":"271"},"goals":{"$numberInt":"3"},"assists":{"$numberInt":"0"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"0"},"cards_yellow":{"$numberInt":"0"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"1"},"assists_per90":{"$numberDouble":"0"},"goals_assists_per90":{"$numberDouble":"1"},"goals_pens_per90":{"$numberDouble":"1"},"goals_assists_pens_per90":{"$numberDouble":"1"},"xg":{"$numberDouble":"1.04"},"npxg":{"$numberDouble":"1.04"},"xa":{"$numberDouble":"0.6"},"xg_per90":{"$numberDouble":"0.34"},"xa_per90":{"$numberDouble":"0.19"},"xg_xa_per90":{"$numberDouble":"0.53"},"npxg_per90":{"$numberDouble":"0.34"},"npxg_xa_per90":{"$numberDouble":"0.53"}},{"season":"2017-2018","age":{"$numberInt":"38"},"squad":"Utrecht","country":"nl NED","comp_level":"1. Dutch Eredivisie","lg_finish":"6th","games":{"$numberInt":"34"},"games_starts":{"$numberInt":"3"},"minutes":{"$numberInt":"872"},"goals":{"$numberInt":"14"},"assists":{"$numberInt":"2"},"pens_made":{"$numberInt":"4"},"pens_att":{"$numberInt":"6"},"cards_yellow":{"$numberInt":"1"},"cards_red":{"$numberInt":"2"},"goals_per90":{"$numberDouble":"1.55"},"assists_per90":{"$numberDouble":"0.22"},"goals_assists_per90":{"$numberDouble":"1.77"},"goals_pens_per90":{"$numberDouble":"1.11"},"goals_assists_pens_per90":{"$numberDouble":"1.33"},"xg":{"$numberDouble":"13.1"},"npxg":{"$numberDouble":"9.09"},"xa":{"$numberDouble":"2.05"},"xg_per90":{"$numberDouble":"1.45"},"xa_per90":{"$numberDouble":"0.22"},"xg_xa_per90":{"$numberDouble":"1.67"},"npxg_per90":{"$numberDouble":"1.01"},"npxg_xa_per90":{"$numberDouble":"1.23"}},{"season":"2018-2019","age":{"$numberInt":"39"},"squad":"Alavés","country":"es ESP","comp_level":"1. La Liga","lg_finish":"16th","games":{"$numberInt":"14"},"games_starts":{"$numberInt":"1"},"minutes":{"$numberInt":"445"},"goals":{"$numberInt":"3"},"assists":{"$numberInt":"4"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"0"},"cards_yellow":{"$numberInt":"1"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"0.75"},"assists_per90":{"$numberDouble":"1"},"goals_assists_per90":{"$numberDouble":"1.75"},"goals_pens_per90":{"$numberDouble":"0.75"},"goals_assists_pens_per90":{"$numberDouble":"1.75"},"xg":{"$numberDouble":"1.39"},"npxg":{"$numberDouble":"1.39"},"xa":{"$numberDouble":"0.21"},"xg_per90":{"$numberDouble":"0.34"},"xa_per90":{"$numberDouble":"0.05"},"xg_xa_per90":{"$numberDouble":"0.39"},"npxg_per90":{"$numberDouble":"0.34"},"npxg_xa_per90":{"$numberDouble":"0.39"}},{"season":"2019-2020","age":{"$numberInt":"40"},"squad":"Defensa y Just","country":"ar ARG","comp_level":"1. Primera Div","lg_finish":"6th","games":{"$numberInt":"17"},"games_starts":{"$numberInt":"6"},"minutes":{"$numberInt":"761"},"goals":{"$numberInt":"10"},"assists":{"$numberInt":"1"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"1"},"cards_yellow":{"$numberInt":"1"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"1.25"},"assists_per90":{"$numberDouble":"0.12"},"goals_assists_per90":{"$numberDouble":"1.37"},"goals_pens_per90":{"$numberDouble":"1.25"},"goals_assists_pens_per90":{"$numberDouble":"1.37"},"xg":{"$numberDouble":"8.54"},"npxg":{"$numberDouble":"8.54"},"xa":{"$numberDouble":"0.18"},"xg_per90":{"$numberDouble":"1.06"},"xa_per90":{"$numberDouble":"0.02"},"xg_xa_per90":{"$numberDouble":"1.08"},"npxg_per90":{"$numberDouble":"1.06"},"npxg_xa_per90":{"$numberDouble":"1.08"}}]}
Example of Structure 2:
{"_id":{"$oid":"5f8ffa19a46b9d4179eafd2c"},"Nome":"Eduino Dykstra","Data nascita":"March 4, 1980","Nazionalità":"Togo","Ruolo":"FW","Link calciatore":"https://fbref.com/en/players/vjLRENdD/Eduino-Dykstra","Ultima stagione":{"season":"2019-2020","age":{"$numberInt":"40"},"squad":"Defensa y Just","country":"ar ARG","comp_level":"1. Primera Div","lg_finish":"6th","games":{"$numberInt":"17"},"games_starts":{"$numberInt":"6"},"minutes":{"$numberInt":"761"},"goals":{"$numberInt":"10"},"assists":{"$numberInt":"1"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"1"},"cards_yellow":{"$numberInt":"1"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"1.25"},"assists_per90":{"$numberDouble":"0.12"},"goals_assists_per90":{"$numberDouble":"1.37"},"goals_pens_per90":{"$numberDouble":"1.25"},"goals_assists_pens_per90":{"$numberDouble":"1.37"},"xg":{"$numberDouble":"8.54"},"npxg":{"$numberDouble":"8.54"},"xa":{"$numberDouble":"0.18"},"xg_per90":{"$numberDouble":"1.06"},"xa_per90":{"$numberDouble":"0.02"},"xg_xa_per90":{"$numberDouble":"1.08"},"npxg_per90":{"$numberDouble":"1.06"},"npxg_xa_per90":{"$numberDouble":"1.08"}},"Penultima stagione":{"season":"2018-2019","age":{"$numberInt":"39"},"squad":"Alavés","country":"es ESP","comp_level":"1. La Liga","lg_finish":"16th","games":{"$numberInt":"14"},"games_starts":{"$numberInt":"1"},"minutes":{"$numberInt":"445"},"goals":{"$numberInt":"3"},"assists":{"$numberInt":"4"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"0"},"cards_yellow":{"$numberInt":"1"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"0.75"},"assists_per90":{"$numberDouble":"1"},"goals_assists_per90":{"$numberDouble":"1.75"},"goals_pens_per90":{"$numberDouble":"0.75"},"goals_assists_pens_per90":{"$numberDouble":"1.75"},"xg":{"$numberDouble":"1.39"},"npxg":{"$numberDouble":"1.39"},"xa":{"$numberDouble":"0.21"},"xg_per90":{"$numberDouble":"0.34"},"xa_per90":{"$numberDouble":"0.05"},"xg_xa_per90":{"$numberDouble":"0.39"},"npxg_per90":{"$numberDouble":"0.34"},"npxg_xa_per90":{"$numberDouble":"0.39"}},"Stagioni":[{"season":"2006-2007","age":{"$numberInt":"27"},"squad":"Atlas","country":"mx MEX","comp_level":"1. Liga MX","lg_finish":"18th","games":{"$numberInt":"2"},"games_starts":{"$numberInt":"0"},"minutes":{"$numberInt":"32"},"goals":{"$numberInt":"0"},"assists":{"$numberInt":"0"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"0"},"cards_yellow":{"$numberInt":"0"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"0"},"assists_per90":{"$numberDouble":"0"},"goals_assists_per90":{"$numberDouble":"0"},"goals_pens_per90":{"$numberDouble":"0"},"goals_assists_pens_per90":{"$numberDouble":"0"},"xg":{"$numberDouble":"0.52"},"npxg":{"$numberDouble":"0.52"},"xa":{"$numberDouble":"0.58"},"xg_per90":{"$numberDouble":"0"},"xa_per90":{"$numberDouble":"0"},"xg_xa_per90":{"$numberDouble":"0"},"npxg_per90":{"$numberDouble":"0"},"npxg_xa_per90":{"$numberDouble":"0"}},{"season":"2007-2008","age":{"$numberInt":"28"},"squad":"Puebla","country":"mx MEX","comp_level":"1. Liga MX","lg_finish":"8th","games":{"$numberInt":"0"},"games_starts":{"$numberInt":"0"},"minutes":{"$numberInt":"0"},"goals":{"$numberInt":"0"},"assists":{"$numberInt":"0"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"0"},"cards_yellow":{"$numberInt":"0"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"0"},"assists_per90":{"$numberDouble":"0"},"goals_assists_per90":{"$numberDouble":"0"},"goals_pens_per90":{"$numberDouble":"0"},"goals_assists_pens_per90":{"$numberDouble":"0"},"xg":{"$numberDouble":"0"},"npxg":{"$numberDouble":"0"},"xa":{"$numberDouble":"0.81"},"xg_per90":{"$numberDouble":"0"},"xa_per90":{"$numberDouble":"0"},"xg_xa_per90":{"$numberDouble":"0"},"npxg_per90":{"$numberDouble":"0"},"npxg_xa_per90":{"$numberDouble":"0"}},{"season":"2008-2009","age":{"$numberInt":"29"},"squad":"Villarreal","country":"es ESP","comp_level":"1. La Liga","lg_finish":"5th","games":{"$numberInt":"3"},"games_starts":{"$numberInt":"0"},"minutes":{"$numberInt":"98"},"goals":{"$numberInt":"0"},"assists":{"$numberInt":"0"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"0"},"cards_yellow":{"$numberInt":"0"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"0"},"assists_per90":{"$numberDouble":"0"},"goals_assists_per90":{"$numberDouble":"0"},"goals_pens_per90":{"$numberDouble":"0"},"goals_assists_pens_per90":{"$numberDouble":"0"},"xg":{"$numberDouble":"0.08"},"npxg":{"$numberDouble":"0.08"},"xa":{"$numberDouble":"0.97"},"xg_per90":{"$numberDouble":"0.08"},"xa_per90":{"$numberDouble":"0.97"},"xg_xa_per90":{"$numberDouble":"1.05"},"npxg_per90":{"$numberDouble":"0.08"},"npxg_xa_per90":{"$numberDouble":"1.05"}},{"season":"2009-2010","age":{"$numberInt":"30"},"squad":"Nantes","country":"fr FRA","comp_level":"1. Ligue 1","lg_finish":"13th","games":{"$numberInt":"21"},"games_starts":{"$numberInt":"20"},"minutes":{"$numberInt":"1040"},"goals":{"$numberInt":"13"},"assists":{"$numberInt":"2"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"1"},"cards_yellow":{"$numberInt":"0"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"1.18"},"assists_per90":{"$numberDouble":"0.18"},"goals_assists_per90":{"$numberDouble":"1.35"},"goals_pens_per90":{"$numberDouble":"1.18"},"goals_assists_pens_per90":{"$numberDouble":"1.36"},"xg":{"$numberDouble":"10.4"},"npxg":{"$numberDouble":"10.4"},"xa":{"$numberDouble":"0.72"},"xg_per90":{"$numberDouble":"0.94"},"xa_per90":{"$numberDouble":"0.06"},"xg_xa_per90":{"$numberDouble":"1"},"npxg_per90":{"$numberDouble":"0.94"},"npxg_xa_per90":{"$numberDouble":"1"}},{"season":"2010-2011","age":{"$numberInt":"31"},"squad":"FC Khimki","country":"ru RUS","comp_level":"1. Russian Premier League","lg_finish":"15th","games":{"$numberInt":"27"},"games_starts":{"$numberInt":"2"},"minutes":{"$numberInt":"570"},"goals":{"$numberInt":"10"},"assists":{"$numberInt":"1"},"pens_made":{"$numberInt":"1"},"pens_att":{"$numberInt":"2"},"cards_yellow":{"$numberInt":"1"},"cards_red":{"$numberInt":"1"},"goals_per90":{"$numberDouble":"1.66"},"assists_per90":{"$numberDouble":"0.16"},"goals_assists_per90":{"$numberDouble":"1.81"},"goals_pens_per90":{"$numberDouble":"1.5"},"goals_assists_pens_per90":{"$numberDouble":"1.66"},"xg":{"$numberDouble":"9.41"},"npxg":{"$numberDouble":"7.37"},"xa":{"$numberDouble":"0.91"},"xg_per90":{"$numberDouble":"1.56"},"xa_per90":{"$numberDouble":"0.15"},"xg_xa_per90":{"$numberDouble":"1.71"},"npxg_per90":{"$numberDouble":"1.22"},"npxg_xa_per90":{"$numberDouble":"1.36"}},{"season":"2011-2012","age":{"$numberInt":"32"},"squad":"Cagliari","country":"it ITA","comp_level":"1. Serie A","lg_finish":"14th","games":{"$numberInt":"6"},"games_starts":{"$numberInt":"0"},"minutes":{"$numberInt":"186"},"goals":{"$numberInt":"1"},"assists":{"$numberInt":"0"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"0"},"cards_yellow":{"$numberInt":"0"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"0.5"},"assists_per90":{"$numberDouble":"0"},"goals_assists_per90":{"$numberDouble":"0.5"},"goals_pens_per90":{"$numberDouble":"0.5"},"goals_assists_pens_per90":{"$numberDouble":"0.5"},"xg":{"$numberDouble":"0.43"},"npxg":{"$numberDouble":"0.43"},"xa":{"$numberDouble":"0.54"},"xg_per90":{"$numberDouble":"0.21"},"xa_per90":{"$numberDouble":"0.27"},"xg_xa_per90":{"$numberDouble":"0.48"},"npxg_per90":{"$numberDouble":"0.21"},"npxg_xa_per90":{"$numberDouble":"0.48"}},{"season":"2012-2013","age":{"$numberInt":"33"},"squad":"Defensa y Just","country":"ar ARG","comp_level":"1. Primera Div","lg_finish":"6th","games":{"$numberInt":"5"},"games_starts":{"$numberInt":"2"},"minutes":{"$numberInt":"220"},"goals":{"$numberInt":"3"},"assists":{"$numberInt":"0"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"0"},"cards_yellow":{"$numberInt":"0"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"1.5"},"assists_per90":{"$numberDouble":"0"},"goals_assists_per90":{"$numberDouble":"1.5"},"goals_pens_per90":{"$numberDouble":"1.5"},"goals_assists_pens_per90":{"$numberDouble":"1.5"},"xg":{"$numberDouble":"1.53"},"npxg":{"$numberDouble":"1.53"},"xa":{"$numberDouble":"0.38"},"xg_per90":{"$numberDouble":"0.76"},"xa_per90":{"$numberDouble":"0.19"},"xg_xa_per90":{"$numberDouble":"0.95"},"npxg_per90":{"$numberDouble":"0.76"},"npxg_xa_per90":{"$numberDouble":"0.95"}},{"season":"2013-2014","age":{"$numberInt":"34"},"squad":"Emmen","country":"nl NED","comp_level":"1. Dutch Eredivisie","lg_finish":"12th","games":{"$numberInt":"14"},"games_starts":{"$numberInt":"12"},"minutes":{"$numberInt":"963"},"goals":{"$numberInt":"5"},"assists":{"$numberInt":"1"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"0"},"cards_yellow":{"$numberInt":"1"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"0.5"},"assists_per90":{"$numberDouble":"0.1"},"goals_assists_per90":{"$numberDouble":"0.6"},"goals_pens_per90":{"$numberDouble":"0.5"},"goals_assists_pens_per90":{"$numberDouble":"0.6"},"xg":{"$numberDouble":"5.32"},"npxg":{"$numberDouble":"5.32"},"xa":{"$numberDouble":"1.09"},"xg_per90":{"$numberDouble":"0.53"},"xa_per90":{"$numberDouble":"0.1"},"xg_xa_per90":{"$numberDouble":"0.63"},"npxg_per90":{"$numberDouble":"0.53"},"npxg_xa_per90":{"$numberDouble":"0.63"}},{"season":"2014-2015","age":{"$numberInt":"35"},"squad":"Munchen Gladbach","country":"de GER","comp_level":"1. Bundesliga","lg_finish":"4th","games":{"$numberInt":"33"},"games_starts":{"$numberInt":"6"},"minutes":{"$numberInt":"967"},"goals":{"$numberInt":"18"},"assists":{"$numberInt":"3"},"pens_made":{"$numberInt":"4"},"pens_att":{"$numberInt":"6"},"cards_yellow":{"$numberInt":"0"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"1.8"},"assists_per90":{"$numberDouble":"0.3"},"goals_assists_per90":{"$numberDouble":"2.1"},"goals_pens_per90":{"$numberDouble":"1.4"},"goals_assists_pens_per90":{"$numberDouble":"1.7"},"xg":{"$numberDouble":"16.2"},"npxg":{"$numberDouble":"13"},"xa":{"$numberDouble":"2.54"},"xg_per90":{"$numberDouble":"1.61"},"xa_per90":{"$numberDouble":"0.25"},"xg_xa_per90":{"$numberDouble":"1.86"},"npxg_per90":{"$numberDouble":"1.3"},"npxg_xa_per90":{"$numberDouble":"1.55"}},{"season":"2015-2016","age":{"$numberInt":"36"},"squad":"Schalke 04","country":"de GER","comp_level":"1. Bundesliga","lg_finish":"12th","games":{"$numberInt":"22"},"games_starts":{"$numberInt":"0"},"minutes":{"$numberInt":"667"},"goals":{"$numberInt":"6"},"assists":{"$numberInt":"3"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"1"},"cards_yellow":{"$numberInt":"1"},"cards_red":{"$numberInt":"1"},"goals_per90":{"$numberDouble":"0.85"},"assists_per90":{"$numberDouble":"0.42"},"goals_assists_per90":{"$numberDouble":"1.27"},"goals_pens_per90":{"$numberDouble":"0.85"},"goals_assists_pens_per90":{"$numberDouble":"1.28"},"xg":{"$numberDouble":"1.26"},"npxg":{"$numberDouble":"1.26"},"xa":{"$numberDouble":"1.71"},"xg_per90":{"$numberDouble":"0.18"},"xa_per90":{"$numberDouble":"0.24"},"xg_xa_per90":{"$numberDouble":"0.42"},"npxg_per90":{"$numberDouble":"0.18"},"npxg_xa_per90":{"$numberDouble":"0.42"}},{"season":"2016-2017","age":{"$numberInt":"37"},"squad":"Sheffield Utd","country":"eng ENG","comp_level":"1. Premier League","lg_finish":"9th","games":{"$numberInt":"5"},"games_starts":{"$numberInt":"3"},"minutes":{"$numberInt":"271"},"goals":{"$numberInt":"3"},"assists":{"$numberInt":"0"},"pens_made":{"$numberInt":"0"},"pens_att":{"$numberInt":"0"},"cards_yellow":{"$numberInt":"0"},"cards_red":{"$numberInt":"0"},"goals_per90":{"$numberDouble":"1"},"assists_per90":{"$numberDouble":"0"},"goals_assists_per90":{"$numberDouble":"1"},"goals_pens_per90":{"$numberDouble":"1"},"goals_assists_pens_per90":{"$numberDouble":"1"},"xg":{"$numberDouble":"1.04"},"npxg":{"$numberDouble":"1.04"},"xa":{"$numberDouble":"0.6"},"xg_per90":{"$numberDouble":"0.34"},"xa_per90":{"$numberDouble":"0.19"},"xg_xa_per90":{"$numberDouble":"0.53"},"npxg_per90":{"$numberDouble":"0.34"},"npxg_xa_per90":{"$numberDouble":"0.53"}},{"season":"2017-2018","age":{"$numberInt":"38"},"squad":"Utrecht","country":"nl NED","comp_level":"1. Dutch Eredivisie","lg_finish":"6th","games":{"$numberInt":"34"},"games_starts":{"$numberInt":"3"},"minutes":{"$numberInt":"872"},"goals":{"$numberInt":"14"},"assists":{"$numberInt":"2"},"pens_made":{"$numberInt":"4"},"pens_att":{"$numberInt":"6"},"cards_yellow":{"$numberInt":"1"},"cards_red":{"$numberInt":"2"},"goals_per90":{"$numberDouble":"1.55"},"assists_per90":{"$numberDouble":"0.22"},"goals_assists_per90":{"$numberDouble":"1.77"},"goals_pens_per90":{"$numberDouble":"1.11"},"goals_assists_pens_per90":{"$numberDouble":"1.33"},"xg":{"$numberDouble":"13.1"},"npxg":{"$numberDouble":"9.09"},"xa":{"$numberDouble":"2.05"},"xg_per90":{"$numberDouble":"1.45"},"xa_per90":{"$numberDouble":"0.22"},"xg_xa_per90":{"$numberDouble":"1.67"},"npxg_per90":{"$numberDouble":"1.01"},"npxg_xa_per90":{"$numberDouble":"1.23"}}]}
On these databases I perform the same operations and calculate the times through an application written in Java. The queries aren’t optimized and that’s not what I’m interested in right now.
But for example, why in a classic find operation performed through “Link calciatore” for both cases, the operation on the database with structure 2 is faster than the operation on the database with structure 1 ??
What affects performance in this case? Structure?