I think there are two problems - but the most important is that the syntax 
select ? from ... where ..

[download]
isn't valid SQL.

?-style placeholders are used to pass variables into WHERE clauses, not to pass literals into the SELECT statement. I suspect that this is why your query only works if you specify the 4.x protocol level, as that does NOT support placeholders.

I'll still take a look at the issue you opened on GitHub, but I suspect that this is really a client side SQL issue more than anything else.

Michael

In reply to Re: fetchall_arrayref hangs with placeholders query with no results by mpeppler
in thread fetchall_arrayref hangs with placeholders query with no results by TieUpYourCamel

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