keys %{ %$ParamValues, %$ParamTypes };

That doesn't make any sense. %{ ... } dereferences a hash reference, but %$ParamValues, %$ParamTypes is not one.

Maybe for (keys %$ParamValues), (keys %$ParamTypes) is meant instead?

Perl 6 - second systems done right

In reply to Re: Problem with hash dereferencing from DBI example by moritz
in thread Problem with hash dereferencing from DBI example by mje

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