Given that you're talking about "quite a few" folders, I think it'd be good
to check up on the theoretical and practical limits for your filesystem of
choice, though - ext2 for example starts getting noticeably slower when you
have a lot more than 10.000 entries in the same directory. One way of
getting around that would be segmenting your database names in blocks of
three or so (so "database" would be stored under dat/aba/se/<datafiles>).
Takes a bit of management, but then you already have something in place to
create the symlinks anyway.
Also, as a matter of manageability, I'd not put your real database dirs
somwhere where there is other stuff - make a separate directory and keep
them all there.
Another point of note, but I suppose you already know that, is that this
will not work with InnoDB unless you have the file-per-table option enabled.
Bier met grenadyn
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Hy die't drinkt, is ras een ezel