I see why it is so slow: you are effectively for every search opening a connection, doing the search for 1 item and then destroying the connection. All this connecting and disconnecting is very time-consuming.

You should put your connection stuff in an initialization subroutine, then prepare your SQL-statement once, using place-holders as follows: " my $sth = $dbh->prepare('select topic FROM table1 WHERE uri LIKE ?');" (added benefit: you don't have to worry about quoting!) and then hand off the $sth-variable and the search-argument to your search-subroutine which calls the execute-method with the search string as its parameter: 

my ($statement_handle, $search_argument)=@_;
$statement_handle->execute($search_argument); ...

[download]

Do you get the idea!

CountZero

"If you have four groups working on a compiler, you'll get a 4-pass compiler." - Conway's Law

In reply to Re^3: How to improve MYSQL search performance of perl? by CountZero
in thread How to improve MYSQL search performance of perl? by nan

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