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<H1>Method call walk-through</H1>
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<LI><H2>Consider a simple prepare call: $dbh->prepare(
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<LI><H2>$dbh is reference to an object in the DBI::db class (regardless of driver)
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<LI><H2>The DBI::db::prepare method is an alias for the DBI dispatch method
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<LI><H2>DBI dispatch calls the drivers own prepare method something like this:
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my $inner_hash_ref = tied %$dbh;
<BR><BR> my $implementor_class = $inner_hash_ref->{ImplementorClass};
<BR> $inner_hash_ref->$implementor_class::prepare(...)
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<LI><H2>Driver code gets the inner hash
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<LI>so it has fast access to the hash contents without tie overheads
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<LI><H2>
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<H2>-</H2>
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