How to improve latex table - latex

Question

In this table, how can I have the upper line that matches between the two tables? I would like to have two tables with the same height. Here is the code that I used to create the table
\documentclass{article}
\usepackage{geometry}
\usepackage{textcomp}
\usepackage{adjustbox}
\usepackage{mathtools}
\usepackage{booktabs} %
\usepackage[group-separator={,}]{siunitx}
\usepackage{changepage}
\newcommand{\undepth}[1]{%
\smash[b]{%
\begin{varwidth}[t]{\linewidth}#1\end{varwidth}
}%
}
\usepackage{makecell}%To keep spacing of text in tables
\begin{document}
\begin{table}[htbp!]
\centering
\footnotesize
\caption{caption}
\begin{tabular}{lSSSS}
\toprule
\makecell[cc]{column1 \\ second line} & \multicolumn{1}{l}{column2} & \multicolumn{1}{l}{column3} & \multicolumn{1}{l}{column4} & \multicolumn{1}{l}{column5} \\
\midrule
A & 4 & 0 & 0.00 & 4 \\
B & 30 & 0 & 0.00 & 30 \\
\bottomrule
\end{tabular}
\quad
\footnotesize
\begin{tabular}{lSS}
\toprule
& {Column1.1 } & {Column2.1}\\
\midrule
A & 0.02 & 0.00 \\
B & 0.04 & 0.00 \\
\bottomrule
\end{tabular}%
\end{table}%
\end{document}

Answer 1

Quick hack:
Put some invisible dummy header of the same height as in the other table
\documentclass{article}
\usepackage{geometry}
\usepackage{textcomp}
\usepackage{adjustbox}
\usepackage{mathtools}
\usepackage{booktabs} %
\usepackage[group-separator={,}]{siunitx}
\usepackage{changepage}
\newcommand{\undepth}[1]{%
\smash[b]{%
\begin{varwidth}[t]{\linewidth}#1\end{varwidth}
}%
}
\usepackage{makecell}%To keep spacing of text in tables
\begin{document}
\begin{table}[htbp!]
\centering
\footnotesize
\caption{caption}
\begin{tabular}{lSSSS}
\toprule
\makecell[cc]{column1 \\ second line} & \multicolumn{1}{l}{column2} & \multicolumn{1}{l}{column3} & \multicolumn{1}{l}{column4} & \multicolumn{1}{l}{column5} \\
\midrule
A & 4 & 0 & 0.00 & 4 \\
B & 30 & 0 & 0.00 & 30 \\
\bottomrule
\end{tabular}
\quad
\footnotesize
\begin{tabular}{lSS}
\toprule
\makecell[cc]{\mbox{} \\ \mbox{}} & {Column1.1 } & {Column2.1}\\
\midrule
A & 0.02 & 0.00 \\
B & 0.04 & 0.00 \\
\bottomrule
\end{tabular}%
\end{table}%
\end{document}
Cleaner solution:
Use only one tabular
\documentclass{article}
\usepackage{geometry}
\usepackage{textcomp}
\usepackage{adjustbox}
\usepackage{mathtools}
\usepackage{booktabs} %
\usepackage[group-separator={,}]{siunitx}
\usepackage{changepage}
\newcommand{\undepth}[1]{%
\smash[b]{%
\begin{varwidth}[t]{\linewidth}#1\end{varwidth}
}%
}
\usepackage{makecell}%To keep spacing of text in tables
\begin{document}
\begin{table}[htbp!]
\centering
\footnotesize
\caption{caption}
\begin{tabular}{lSSSSSS}
\cmidrule[\heavyrulewidth](r){1-5}\cmidrule[\heavyrulewidth](l){6-7}
\makecell[cc]{column1 \\ second line} & \multicolumn{1}{l}{column2} & \multicolumn{1}{l}{column3} & \multicolumn{1}{l}{column4} & \multicolumn{1}{l}{column5} & {Column1.1 } & {Column2.1} \\
\cmidrule(r){1-5}\cmidrule(l){6-7}
A & 4 & 0 & 0.00 & 4 & 0.02 & 0.00 \\
B & 30 & 0 & 0.00 & 30 & 0.04 & 0.00 \\
\cmidrule[\heavyrulewidth](r){1-5}\cmidrule[\heavyrulewidth](l){6-7}
\end{tabular}%
\end{table}%
\end{document}