columnlines="solid dashed"
$\begin{array}{ccc}\text{a}& \text{b}& \text{c}\\ \text{d}& \text{e}& \text{f}\\ \text{g}& \text{h}& \text{i}\end{array}$
columnlines="dashed solid"
$\begin{array}{ccc}\text{a}& \text{b}& \text{c}\\ \text{d}& \text{e}& \text{f}\\ \text{g}& \text{h}& \text{i}\end{array}$