Cite only first author and year

Question

\documentclass{article}
\usepackage{mwe}
\usepackage{biblatex}
\addbibresource{biblatex-examples.bib}
\begin{document}
\cite*{kastenholz}, \citeyear{kastenholz}
\end{document}

I am look for a way to cite only the first author (or more if it is not unique) and the year with one command. Kind of fullcite{} but the other way around. I couldn't find this in the docu.

I need this on a specific part of the paper. The this should work "local" and not affect any global settings of the document. I want to use this in a table to reference papers where the data comes from but with minimal space usage in the table.

Answer 1

You could create a new cite command, from the ones available, to do what you want.

\documentclass{article}
\usepackage{mwe}
\usepackage{biblatex}
\addbibresource{biblatex-examples.bib}

\newcommand\mycite[1]{\AtNextCite{\defcounter{maxnames}{1}}\citeauthor{#1}, \citeyear{#1}}

\begin{document}
\mycite{kastenholz}

\end{document}

Update: As pointed out by moewe in the comments, this approach, albeit simple, has relevant limitations. It won't deal with pre- and post-notes (though it could be adapted to deal with one of them) and also not handle multiple entries. If this is enough for your case, then fine, otherwise, for a more general solution using \DeclareCiteCommand is preferred (see https://tex.stackexchange.com/a/398595/105447).

Answer 2

It looks like you want an author-year type citation. So load biblatex with the authoryear style.

If you really want only the first author to show up, then use maxnames=1 or maxcitenames=1 which will render the example citation as Kastenholz et al. (2006).

\documentclass{article}
\usepackage{mwe}
\usepackage[style=authoryear]{biblatex}
\addbibresource{biblatex-examples.bib}
\begin{document}
\textcite{kastenholz}
\end{document}

Answer 3

You can define a new command for that like this

\documentclass{article}
\usepackage{mwe}
\usepackage[style=numeric, labeldateparts]{biblatex}
\addbibresource{biblatex-examples.bib}

\newbibmacro{aycite}{%
  \defcounter{maxnames}{1}%
  \ifnameundef{labelname}
    {\printfield{labeltitle}%
     \setunit{\printdelim{nonameyeardelim}}}
    {\printnames{labelname}%
     \setunit{\printdelim{nameyeardelim}}}
  \printtext[bibhyperref]{\printlabeldateextra}}

\DeclareCiteCommand{\aycite}
  {\usebibmacro{prenote}}%
  {\usebibmacro{citeindex}%
   \usebibmacro{aycite}}
  {\multicitedelim}
  {\usebibmacro{postnote}} 

\begin{document}
\aycite{kastenholz}
\end{document}

I would have preferred to use mincitenames=1, maxcitenames=1, uniquelist=true instead of \defcounter{maxnames}{1}, but that would have been against your wish to not change any settings. It is only possible to fulfil the 'or more if it is not unique' desideratum with mincitenames=1, maxcitenames=1, uniquelist=true. Since you use a numeric style it is unlikely that the three options would impact other citations, but not impossible (if you use \textcite there could be changes, if you only use \cite there should not be a problem).

I introduced the labeldateparts option, but that does not impact other commands.