At the risk of asking a stupid question, we already have optimizer
statistics on expression indexes. In what sense are we using this for
multi-variate statistics, and in what sense can't we.
FYI, I just wrote a blog post about expression index statistics:
http://momjian.us/main/blogs/pgblog/2017.html#February_20_2017
-- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB
http://enterprisedb.com
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