Some things that might have an influence on the benchmarks, depending on the RDBMS:

If you just test for existence, you can use the exists function in a bit of sql-code:

if not exists (select * from depend where usedby='Depend::Module' AND 
+uses='DBI')
begin
  insert ....
end

[download]

An index on the columns in where clause might have a huge impact if you use count(*).

In reply to Re: How to count rows using DBI & mysql - Performance results by busunsl
in thread How to count rows using DBI & mysql - Performance results by Brovnik

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