What led you to choose the ? operator for the FOLLOWED BY semantics?
It doesn't seem a terribly natural choice -- most other things seems to
use ? as some sort of wildcard. What about something like "...", so you
would do
SELECT q @@ to_tsquery('fatal ... error');
and
SELECT q @@ (tsquery 'fatal' ... tsquery 'error');
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Álvaro Herrera http://www.2ndQuadrant.com/
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