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author | Peter Eisentraut <peter@eisentraut.org> | 2019-03-30 08:13:09 +0100 |
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committer | Peter Eisentraut <peter@eisentraut.org> | 2019-03-30 08:15:57 +0100 |
commit | fc22b6623b6b3bab3cb057ccd282c2bfad1a0b30 (patch) | |
tree | cda5092955ece5d547d5517ed56a3d480f199d25 /src/backend/utils/cache/relcache.c | |
parent | 6b8b5364ddd0e4d882562615c6b6c28638ade9f2 (diff) |
Generated columns
This is an SQL-standard feature that allows creating columns that are
computed from expressions rather than assigned, similar to a view or
materialized view but on a column basis.
This implements one kind of generated column: stored (computed on
write). Another kind, virtual (computed on read), is planned for the
future, and some room is left for it.
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/b151f851-4019-bdb1-699e-ebab07d2f40a@2ndquadrant.com
Diffstat (limited to 'src/backend/utils/cache/relcache.c')
-rw-r--r-- | src/backend/utils/cache/relcache.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c index 12f813f0bc5..64f3c2e8870 100644 --- a/src/backend/utils/cache/relcache.c +++ b/src/backend/utils/cache/relcache.c @@ -515,6 +515,7 @@ RelationBuildTupleDesc(Relation relation) constr = (TupleConstr *) MemoryContextAlloc(CacheMemoryContext, sizeof(TupleConstr)); constr->has_not_null = false; + constr->has_generated_stored = false; /* * Form a scan key that selects only user attributes (attnum > 0). @@ -567,6 +568,8 @@ RelationBuildTupleDesc(Relation relation) /* Update constraint/default info */ if (attp->attnotnull) constr->has_not_null = true; + if (attp->attgenerated == ATTRIBUTE_GENERATED_STORED) + constr->has_generated_stored = true; /* If the column has a default, fill it into the attrdef array */ if (attp->atthasdef) @@ -3281,6 +3284,7 @@ RelationBuildLocalRelation(const char *relname, Form_pg_attribute datt = TupleDescAttr(rel->rd_att, i); datt->attidentity = satt->attidentity; + datt->attgenerated = satt->attgenerated; datt->attnotnull = satt->attnotnull; has_not_null |= satt->attnotnull; } |