Hello,

I was doing some experimenting to try and reduce the execution time of a query 
used in a PreparedStatement. To do that, I normally use the Prepare and Execute 
statements of Postgresql. What I notice is that explicit casting has a 
considerable performance impact. So using the good data types in the Prepare 
and avoid casting gives much better performance. My questions are :

  *   Does the implementation of PreparedStatment in Postgresql driver uses the 
Prepare and Execute?
  *   If so why I cannot see the Prepare and the parameters type in the logs if 
not how can I simulate the same mechanism from the command line?
  *   Is it possible to avoid explicit casting without getting the error could 
not determine data type of parameter?

The query is bit complex on large tables but the main part is : where cast($1 
as text) is null or cast($2 as text) is null or ( date_field < cast(cast($3 as 
text) as date) and date_field > cast(cast($4 as text) as date) )

Thanks for your help.

Sabiq

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