pgsql: Disallow creation of indexes on system columns (except for OID).

Disallow creation of indexes on system columns (except for OID).

Although OID acts pretty much like user data, the other system columns do
not, so an index on one would likely misbehave. And it's pretty hard to
see a use-case for one, anyway. Let's just forbid the case rather than
worry about whether it should be supported.

David Rowley

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/c34df8a003c3e478d70e8251bd2a24d710b297d4

Modified Files
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src/backend/commands/indexcmds.c | 37 ++++++++++++++++++++++++++++++
src/test/regress/expected/create_index.out | 16 +++++++++++++
src/test/regress/sql/create_index.sql | 19 +++++++++++++++
3 files changed, 72 insertions(+)