\documentclass{datenschleuder}

\usepackage{pgfplotstable}
\usepackage{booktabs}
%\usepackage{xcolor} 
\usepackage{colortbl}
\usepackage{pdflscape} %testing only
\usepackage{hyperref}
\usepackage{rotating}
\pgfplotsset{compat=1.14}
\begin{document}
%%%%\begin{sidewaysfigure}[h]
\tiny
\pgfplotstableread[col sep=semicolon]{adressliste.csv}{\loadedtable}
\pgfplotstablecreatecol[
        columns={Erfa,Adresse,Tag,Bemerkung},
        create col/assign/.code={%
                \edef\entry{\thisrow{Erfa}, \thisrow{Adresse}
        }%
        \pgfkeyslet{/pgfplots/table/create col/next content}\entry
}]{Test}{\loadedtable}

%%\pgfplotstableset{
%%        columns/Erfa/.style={string type},
%%        columns/Ort/.style={string type},
%%        columns/Tag/.style={
%%                string type,
%%                column name={Tag, Uhrzeit}
%%        },
%%        columns/Adresse/.style={string type},
%%        columns/Bemerkung/.style={string type,
%%                assign cell content/.code={
%%                        \pgfkeyssetvalue{/pgfplots/table/@cell content}{\url{##1}}
%%                },
%%        },
%%        columns/Test/.style={%
%%                string type,
%%                assign cell content/.code={
%%                        \pgfkeyssetvalue{/pgfplots/table/@cell content}{\textit{##1}}
%%                },
%%        }%
%%}
%%
%%\pgfplotstabletypeset[%
%%        columns={Erfa,Test,Bemerkung,Tag},
%%        every head row/.style={before row=\toprule, after row=\midrule},
%%        every last row/.style={after row=\midrule},
%%        every even row/.style={
%%                before row={
%%                        \rowcolor{lightgray}
%%                },
%%        },
%%%        columns/Test/.style={%
%%%                string type,
%%%                postproc cell content/.append style={%
%%%                        /pgfplots/table/@cell content/.add={}{},
%%%                },%
%%%        }%
%%]{\loadedtable}

\pgfplotstableset{
        columns/Erfa/.style={string type},
        columns/Ort/.style={string type},
        columns/Tag/.style={
                string type,
                column name={Tag, Uhrzeit}
        },
        columns/Adresse/.style={string type},
        columns/Bemerkung/.style={string type,
                assign cell content/.code={
                        \pgfkeyssetvalue{/pgfplots/table/@cell content}{\url{##1}}
                },
        },
        create on use/Zusammen/.style={
                string type,
                create col/assign/.code={
                        \getthisrow{Erfa}\erfa
                        \getthisrow{Ort}\ort
                        \edef\entry{ {\erfa~wohnt im \ort}}%
                        \pgfkeyslet{/pgfplots/table/create col/next content}\entry
                },

        },
        columns/Zusammen/.style={string type},
}
\pgfplotstabletypeset[
    col sep=semicolon,
        columns={Erfa,Ort},
                        %
    empty cells with={--}, % replace empty cells
    every head row/.style={before row=\toprule, after row=\midrule},
    every last row/.style={after row=\midrule},
    every even row/.style={
        before row={
            \rowcolor{lightgray}
        },
    },
]{adressliste.csv}
%%%%\end{sidewaysfigure}%
%%%%\normalsize
\end{document}