pgsql: Handle NULL fields in WRITE_INDEX_ARRAY

Handle NULL fields in WRITE_INDEX_ARRAY

Unlike existing WRITE_*_ARRAY macros, WRITE_INDEX_ARRAY needs to
handle the case that the field is NULL. We already have the
convention to print NULL fields as "<>", so we do that here as well.
There is currently no corresponding read function for this, so reading
this back in is not implemented, but it could be if needed.

Reported-by: Richard Guo <guofenglinux(at)gmail(dot)com>
Reviewed-by: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Discussion: https://www.postgresql.org/message-id/flat/CAMbWs4-LN%3DbF8f9eU2R94dJtF54DfDvBq%2BovqHnOQqbinYDrUw%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/9ddf251f94090cebf1bd8fc18396cb8a4b580d04

Modified Files
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src/backend/nodes/outfuncs.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)