pgsql: Add a graph pattern variable only once

Add a graph pattern variable only once

An element pattern variable may be repeated in the path pattern.
GraphTableParseState maintains a list of all variable names used in
the graph pattern. Add a new variable name to that list only when it
is not present already. This isn't a problem right now, but it could
be in the future.

Author: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Discussion: /messages/by-id/CAExHW5tR4O0vjeqTCPr2VB5pYjNYbJgbCBEQf63NtU5Pz1MiOQ@mail.gmail.com

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/288ae968726ebaca587a446041fe0e0a6377562d

Modified Files
--------------
src/backend/parser/parse_graphtable.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)