Two table counters and hyperref links

Question

I have a document with two sets of tables. The first set, numbered 1 to 5, are in the main body of the text. The second, numbered 1 to 3, are in an appendix.

When I use \ref to link to one of the tables in the appendix, the hyperlink in the PDF file links to the corresponding table in the main section (so a link to appendix table 1 links to main table 1). This warning message is provided:

pdfTeX warning (ext4): destination with the same identifier (name{table.1}) 
   has been already used, duplicate ignored

Clearly this is a counter problem: when I reset the table counter in the appendix, there are two tables with a counter of 1 and hyperref just points to the first one.

Related problems have been discussed on this forum, and a number of discussions can be found online, but I haven't been able to figure out a solution to this particular problem. (It seems more straightforward to fix the problem for page numbers.) Also, I get the sense that the aliascnt package could work here, but I can't figure out how to make it work.

Answer 1

Indeed, the problem comes from link anchors not having unique names. To provide those unique names, you can appropriately redefine \theHtable to guarantee that it will expand to a unique value (despite the counter resetting); for example:

\documentclass{article}
\usepackage{hyperref}

\begin{document}

\section{test}
\renewcommand*{\theHtable}{\arabic{table}} 
\begin{table}
  \centering Test
  \caption{test1}\label{fig:test1}
\end{table}

\begin{table}
  \centering Test
  \caption{test2}\label{fig:test2}
\end{table}

\begin{table}
  \centering Test
  \caption{test3}\label{fig:test3}
\end{table}

\appendix

\setcounter{table}{0}
\renewcommand*{\theHtable}{\arabic{section}.\arabic{table}} 

\begin{table}
  \centering Test
  \caption{test4}\label{fig:test4}
\end{table}

\begin{table}
  \centering Test
  \caption{test5}\label{fig:test5}
\end{table}

\ref{fig:test1}\ref{fig:test2}\ref{fig:test3}\ref{fig:test4}\ref{fig:test5}

\end{document}