I don't have the table format

[RikkuKaiser]

I am using ubuntu 20.04 when I make a query to the database it returns a simple format

[Borvik]

This likely has to do with your theme.

The background color of the results view is this:

background-color: var(--vscode-editor-background, var(--theme-background));

and the cell border colors are this:

border-color: var(--vscode-panel-border);

my guess is that for you, those colors end up being the same.