I was getting the same error for DBD::ODBC connecting to MSSQL Server and learned that some DBI drivers can only support one open statement per DBI connection. This may not be the same root cause in Jenda's problem above, however...

My problem was related to nested queries. Using multiple connections was the easiest solution. Here's the answer on the templates list archive.

--Solo

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I think my eyes are getting better. Instead of a big dark blur, I see a big light blur.