When using longtable, my table counter starts from 2 rather than 1. Why?

Question

When using longtable, my table counter starts from 2 rather than 1. Why?

\documentclass[12pt]{article}

\usepackage{xcolor}
\usepackage{array,booktabs,longtable}
%\extrarowheight5pt

\begin{document}

\begin{table}
\begin{longtable}{@{}p{0.2\linewidth}p{0.4\linewidth}p{0.4\linewidth}@{}}
\toprule
Options
    & Values
        & Descriptions\\
\midrule
%
\verb|PtNameMath|
    & {\color{blue}\verb|true|}, \verb|false|
        &   whether the node label is in math mode.\\
%
\bottomrule 
\end{longtable}
\caption{\texttt{\textbackslash pstGeonode} options.}
\label{tab:GeoNodeOptions}
\end{table}


\end{document}

Answer 1

This example:

\documentclass[12pt]{article}

\usepackage{xcolor}
\usepackage{booktabs,longtable}

\begin{document}

\begin{longtable}{@{}p{0.2\linewidth}p{0.4\linewidth}p{0.4\linewidth}@{}}
\toprule
Options
    & Values
        & Descriptions\\
\midrule
%
\verb|PtNameMath|
    & {\color{blue}\verb|true|}, \verb|false|
        &   whether the node label is in math mode.\\
%
\bottomrule 
\caption{\texttt{\textbackslash pstGeonode} options.}
\label{tab:GeoNodeOptions}
\end{longtable}    

\end{document}

is perfectly working and the result is:

The issue of the wrong caption number is due to the fact that you nested a longtable environment into a table one and this increase twice the counter.

Citing the documentation:

It also shares some features with the table environment. In particular it uses the same counter, table, and has a similar \caption command.