# why there is space in the borders of the table?

I used the following code to draw the table, however, there is blank space in the border. the lines are not connected. May someone help me?

\usepackage{tikz}
\usetikzlibrary{
shapes.geometric,
positioning,
fit,
calc
}
\usepackage{array}
\usetikzlibrary{decorations.markings}
\newcommand*{\Shift}{0.6ex}
\usepackage{fancyvrb}
\usepackage{listings}
\usepackage{etex}
\usepackage{amsmath, amssymb, proof} % mathabx,
\usepackage{ctable}
\usepackage{multirow}
\usepackage{bigstrut}
\usepackage{lipsum}

\usepackage[ruled,vlined,linesnumbered]{algorithm2e}

% GRAPHICS

\usepackage{pgf}
\usepackage{graphicx}
\usepackage{tikz}
\usepackage{pgfplots}
\usepackage{verbatim}
\usetikzlibrary{arrows,automata,positioning,shapes,patterns}

\usepackage{mathtools}
\usepackage{hyperref}

\usepackage{scalefnt}
\begin{table}[h]
\centering

\begin{tabular}%{@{}p{0.7in}c@{\hspace{0.5em}}c@{\hspace{0.5em}}c@{\hspace{0.5em}}c}
{| >{\centering\arraybackslash}m{0.7in} | >{\centering\arraybackslash}m{0.7in} |>{\centering\arraybackslash}m{0.7in} |}
\toprule
{\small{Response Time}} & \small{Availability} & \small{Throughput} \\
\midrule
$\sum\limits_{i=1}^n q(\si)$  &  $\prod\limits_{i=1}^n q(\si)$  & $\min\limits_{i=1}^n q(\si)$   \\
\bottomrule
\end{tabular}%
\caption{Aggregation Function}
\label{tab:compositionalStructure}%
\end{table}


![enter image description here][1]

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You haven't said (please always post complete documents showing all packages used) but you are using booktabs. booktabs as an explicit, documented design aim, is incompatible with vertical rules. You need to choose to either have vertical rules or use that package.
@william007 Your example is still not a complete document, if I add \documentclass{article} and define \si so that it runs without error then the log file confirms booktabs is being used (/usr/local/texlive/2012/texmf-dist/tex/latex/booktabs/booktabs.sty (ctable loads booktabs) – David Carlisle Feb 25 '13 at 19:04