pgsql: Make more use of makeColumnDef()

Make more use of makeColumnDef()

Since we already have it, we might as well make full use of it,
instead of assembling ColumnDef by hand in several places.

Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://www.postgresql.org/message-id/flat/52a125e4-ff9a-95f5-9f61-b87cf447e4da@eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/1fa9241bdd0e44d2b602b2dd4b6f0a4d0d402e76

Modified Files
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src/backend/commands/sequence.c    | 29 ++++++++-------------------
src/backend/commands/tablecmds.c   | 15 ++------------
src/backend/parser/parse_utilcmd.c | 40 +++++++++-----------------------------
3 files changed, 19 insertions(+), 65 deletions(-)