I'm using psqlodbc on Windows to perform a query that returns on the order of 1 million rows.
I have noticed that, when the DSN is configured to use SSL, the query runs very slow, like three times slower.
However, if I delete libpq.dll from the psqlodbc installation directory, the slowdown in the SSL-secured query is much less (only about 10-20% compared to the unsecured query).
I have tried several of the latest versions of the driver, and the same thing happens in all.
Several doubts:
- I surmise that the absence of libpq forces the driver to use Windows' sspi service to handle the SSL, is that correct?
- Is it normal that using sspi is that much faster?
- Is there a way, other than deleting libpq.dll, to force the use of sspi on Windows when using the compiled distribution of the driver?