pgsql: Property references are preferred over regular column references

Property references are preferred over regular column references

When a ColumnRef can be resolved as a graph table property reference
and a lateral table column reference prefer the graph table property
reference since element pattern variables in the GRAPH_TABLE clause
form the innermost namespace.

Author: Ashutosh Bapat <ashutosh(dot)bapat(dot)oss(at)gmail(dot)com>
Reviewed-by: Henson Choi <assam258(at)gmail(dot)com>
Discussion: https://www.postgresql.org/message-id/CAExHW5u6AoDfNg4%3DR5eVJn_bJn%3DC%3DwVPrto02P_06fxy39fniA%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/c5b3253b8abd7b89689d1095c7c1154b784ca9c9

Modified Files
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src/backend/parser/parse_expr.c | 14 ++++++++++----
src/test/regress/expected/graph_table.out | 18 ++++++++++++++----
src/test/regress/sql/graph_table.sql | 6 +++++-
3 files changed, 29 insertions(+), 9 deletions(-)