From fc22b6623b6b3bab3cb057ccd282c2bfad1a0b30 Mon Sep 17 00:00:00 2001 From: Peter Eisentraut Date: Sat, 30 Mar 2019 08:13:09 +0100 Subject: 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 Reviewed-by: Pavel Stehule Discussion: https://www.postgresql.org/message-id/flat/b151f851-4019-bdb1-699e-ebab07d2f40a@2ndquadrant.com --- src/backend/parser/parse_relation.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'src/backend/parser/parse_relation.c') diff --git a/src/backend/parser/parse_relation.c b/src/backend/parser/parse_relation.c index f3b6d193aa7..0640d11fac7 100644 --- a/src/backend/parser/parse_relation.c +++ b/src/backend/parser/parse_relation.c @@ -731,6 +731,17 @@ scanRTEForColumn(ParseState *pstate, RangeTblEntry *rte, const char *colname, colname), parser_errposition(pstate, location))); + /* + * In generated column, no system column is allowed except tableOid. + */ + if (pstate->p_expr_kind == EXPR_KIND_GENERATED_COLUMN && + attnum < InvalidAttrNumber && attnum != TableOidAttributeNumber) + ereport(ERROR, + (errcode(ERRCODE_INVALID_COLUMN_REFERENCE), + errmsg("cannot use system column \"%s\" in column generation expression", + colname), + parser_errposition(pstate, location))); + if (attnum != InvalidAttrNumber) { /* now check to see if column actually is defined */ @@ -1257,6 +1268,7 @@ addRangeTableEntry(ParseState *pstate, rte->selectedCols = NULL; rte->insertedCols = NULL; rte->updatedCols = NULL; + rte->extraUpdatedCols = NULL; /* * Add completed RTE to pstate's range table list, but not to join list @@ -1328,6 +1340,7 @@ addRangeTableEntryForRelation(ParseState *pstate, rte->selectedCols = NULL; rte->insertedCols = NULL; rte->updatedCols = NULL; + rte->extraUpdatedCols = NULL; /* * Add completed RTE to pstate's range table list, but not to join list @@ -1407,6 +1420,7 @@ addRangeTableEntryForSubquery(ParseState *pstate, rte->selectedCols = NULL; rte->insertedCols = NULL; rte->updatedCols = NULL; + rte->extraUpdatedCols = NULL; /* * Add completed RTE to pstate's range table list, but not to join list @@ -1670,6 +1684,7 @@ addRangeTableEntryForFunction(ParseState *pstate, rte->selectedCols = NULL; rte->insertedCols = NULL; rte->updatedCols = NULL; + rte->extraUpdatedCols = NULL; /* * Add completed RTE to pstate's range table list, but not to join list @@ -1733,6 +1748,7 @@ addRangeTableEntryForTableFunc(ParseState *pstate, rte->selectedCols = NULL; rte->insertedCols = NULL; rte->updatedCols = NULL; + rte->extraUpdatedCols = NULL; /* * Add completed RTE to pstate's range table list, but not to join list @@ -1811,6 +1827,7 @@ addRangeTableEntryForValues(ParseState *pstate, rte->selectedCols = NULL; rte->insertedCols = NULL; rte->updatedCols = NULL; + rte->extraUpdatedCols = NULL; /* * Add completed RTE to pstate's range table list, but not to join list @@ -1881,6 +1898,7 @@ addRangeTableEntryForJoin(ParseState *pstate, rte->selectedCols = NULL; rte->insertedCols = NULL; rte->updatedCols = NULL; + rte->extraUpdatedCols = NULL; /* * Add completed RTE to pstate's range table list, but not to join list @@ -1983,6 +2001,7 @@ addRangeTableEntryForCTE(ParseState *pstate, rte->selectedCols = NULL; rte->insertedCols = NULL; rte->updatedCols = NULL; + rte->extraUpdatedCols = NULL; /* * Add completed RTE to pstate's range table list, but not to join list -- cgit v1.2.3