Biblatex: how to "fullcite" the first occurences and "cite" the others

Question

I am using xelatex and biblatex (backend biber), and I would like the \cite command to act as \fullcite whenever a reference is cited the first time. For instance, say my document is as follows:

This is the first time I cite \cite{book1},
and this is the second time I cite \cite{book1}.
This is the first time I cite \cite{book2}.

Then I would like it to be compiled as

This is the first time I cite \fullcite{book1},
and this is the second time I cite \cite{book1}.
This is the first time I cite \fullcite{book2}.

Possibly, I would prefer defining a new command, e.g. \mycite, so that I can still use the original \cite.

Besides, how to tell \fullcite which fields to print, without interfering with how the references in the bibliography are shown?

Answer 1

For the first question, you can use the preamble option:

\usepackage[backend=biber,…,citestyle=verbose,…]{biblatex}

It does exactly what you want; verbosecan be replaced by one of the derived styles:

verbose-ibid, verbose-note, verbose-inote, verbose-trad1, verbose-trad2, verbose-trad3,

as defined in §3.3.1 of the doc.

For the second question, probably you should define some \myfullcite command. I can say no more, as you do not give any details.