Improve user-defined-aggregates documentation.
On closer inspection, that two-element initcond value seems to have been
a little white lie to avoid explaining the full behavior of float8_accum.
But if people are going to expect the examples to be exactly correct,
I suppose we'd better explain. Per comment from Thom Brown.
Branch
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REL9_0_STABLE
Details
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http://git.postgresql.org/pg/commitdiff/03c77337209f0b2b3059d6ee9df2f94c6f66d910
Modified Files
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doc/src/sgml/xaggr.sgml | 16 +++++++++++-----
1 files changed, 11 insertions(+), 5 deletions(-)