Xjyuk

I am very new to Latex. Can you help me with this diagram? I have been trying hard but still, I cannot make any progress. I will export the image from Inkscape to tikZ. If it works, I’ll publish the answer myself.

mwe (Credits to @Marmot)

 documentclass[tikz,border=3.14mm]standalone
usetikzlibrarypositioning,fit,shadows.blur,shapes.geometric,calc
begindocument
begintikzpicture[font=sffamily,
 regentonne/.style=cylinder,aspect=0.3,draw,shape border rotate=90]
 beginscope[nodes=align=center,fill=white,blur shadow]
 node[regentonne] (A) MovieLens\ Database;
 node[regentonne,right=10em of A] (B) MovieLens\ Features;
 path (A) -- (B) node[midway,above=9em,regentonne] (C) User--Item\ Pairs;
 node[anchor=north west,draw,minimum width=8em] at (B.west|-C.north) (D) Collaborative\
 Filter\ Algorithms\[2em]SVD\ KNN;
 path let p1=($(D.south)-(B.north)$) in node[anchor=north west,draw,minimum width=8em] at 
 ([yshift=-y1]B.south-|D.west) (E) Error Prediction\ Models\[2em]
 SVD\ KNN;
 node[right=5em of E,draw] (F) Algorithm\ Selection;
 node[below=5em of F,draw] (G) Predicted Rating;
 beginscope[>=stealth,thick,->]
 draw[rounded corners] (A) -| (C);
 draw[rounded corners] (D.-10) -| (F);
 path (A) edge (B) (B) edge (B|-E.north) (D.-60) edge (E.north-|D.-60)
 (E) edge (F) (F) edge (G) (C.east) edge (C.east-|D.west);
 endscope
 endscope
 path ($(F)+(5.5em,0)$) coordinate (aux);
 node[draw,inner sep=0.5em,dashed,fit=(B) (E) (F) (aux),
 label=[anchor=north east]north east:Meta learner] (F1) ;
 node[draw,inner sep=0.5em,dashed,fit=(C) (E) (F1),
 label=[anchor=north east]north east:Recommender system] (F2) ;
endtikzpicture
enddocument

You need to fill in some of the texts yourself.

documentclass[tikz,border=3.14mm]standalone
usepackagetikzlings
usetikzlibrarypositioning,shadows.blur,shapes.geometric,calc,fit
tikzsetdatabase/.style=cylinder,aspect=2,draw,fill,shape border rotate=90,path picture=
draw[white] let p1=($(path picture bounding box.north east)-(path picture bounding
box.south west)$) in 
foreach XX in 1,2,3 ([yshift=-XX*y1/4]path picture bounding box.north west) 
arc(180:360:x1/2 and 0.25*x1/2);

begindocument
begintikzpicture[font=sffamily]
 beginscope[nodes=draw,align=center,local bounding box=Canada]
 node[database,minimum size=6em,label=[name=DB]below:DB] (db);
 node[draw=blue,anchor=north] (MT) at ([xshift=-7em]db.west) Model\ Training;
 node[draw=green!60!black,above=2em of MT] (PM) Prediction\
 Model;
 path (PM.north west) + (-3em,5em) (MT) + (0,-5em) (db.east) + (1em,0);
 endscope
 draw (Canada.south west) rectangle (Canada.north east) node[below
 left]Recommendation Engine;
 path let p1=($(Canada.north)-(Canada.south)$) in 
 node[left=1em of Canada,minimum height=y1,inner ysep=0pt,draw] (Client) Client;
 koala[shift=([xshift=-5em,yshift=-3em]Client.west)]
 beginscope[thick,-latex,nodes=fill=white,align=center]
 draw (Client.71) -| (db) node[pos=0.3]
 user feedback\ (dots);
 draw[green!60!black] (db.west) -- ++(-2em,0) |- (PM) 
 node[pos=0.2]bla;
 draw[green!60!black] (PM.west) -- ++(-1em,0) |- (Client.-70) 
 node[pos=0.2]bla;
 draw[dashed,blue!80!black] (DB.south) -- ++ (0,-1.5em) -| (MT)
 node[pos=0.2]User history;
 draw[dashed,blue!80!black] (MT) -- (PM);
 endscope
endtikzpicture
enddocument