Of course, the problem can be "solved" by inserting a false "}" inside a comment:

A simpler solution would have been to escape the delimiter like you would do with single-line string literals.

#sub _DBLoad \{
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However, single-quoted here-docs are even simpler. They remove the need to escape slashes and delimiters.

      eval <<'__EOI__';
        ...
__EOI__
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For example, the output of the following two snippets differ only in the leading newline.

print q{
   foo \{ \} \\\\ bar
};
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print <<'__EOI__';
   foo { } \\ bar
__EOI__
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Update: Added escaping solution.