pgsql: Doc: add an example of a self-referential foreign key to ddl.sgm - Mailing list pgsql-committers

Doc: add an example of a self-referential foreign key to ddl.sgml.

While we've always allowed such cases, the documentation didn't
say you could do it.

Discussion: https://postgr.es/m/161969805833.690.13680986983883602407@wrigleys.postgresql.org

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/7dcec3ed45d5a128fcc8bce23b9a2879fc520aa0

Modified Files
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doc/src/sgml/ddl.sgml | 28 ++++++++++++++++++++++++++--
1 file changed, 26 insertions(+), 2 deletions(-)