Attached is a patch for $subject. It's based on Serge Reilau's patch of
about a year ago, taking into account comments made at the time. with
bitrot removed and other enhancements such as documentation.
Essentially it stores a value in pg_attribute that is used when the
stored tuple is missing the attribute. This works unless the default
expression is volatile, in which case a table rewrite is forced as
happens now.
Comments welcome.
cheers
andrew
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Andrew Dunstan https://www.2ndQuadrant.com
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