\documentclass{article}
\usepackage{filecontents}
\usepackage{datatool}

\begin{filecontents*}{example1.csv}
title;value
test1;1
test2;
test3;3
test4;2
\end{filecontents*}
\begin{filecontents*}{example2.csv}
title;value
test1;1
test2;2
test3;3
test4;4
\end{filecontents*}

\begin{document}
    \DTLsetseparator{;}%
    \DTLloaddb{a}{example1.csv}
    \DTLminforcolumn{a}{value}{\minValueFirstExample}
    
    \DTLsetseparator{;}%
    \DTLloaddb{b}{example2.csv}
    \DTLminforcolumn{b}{value}{\minValueSecondExample}
    
    Min Value1: \minValueFirstExample\\ %Should be 1 and not 2
    Min Value2: \minValueSecondExample %Is correct
\end{document}
  