pgsql: Remove ancient special case code for adding oid columns

Remove ancient special case code for adding oid columns

The special handling of negative attribute numbers in
ATExecAddColumn() was introduced to support SET WITH OIDS (commit
6d1e361852).  But that feature doesn't exist anymore, so we can revert
to the previous, simpler version.  In passing, also remove an obsolete
comment about OID support.

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/5eaa0e92ee2f94994c55c02d01b3feabc6c35f54

Modified Files
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src/backend/commands/tablecmds.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)