Re: SQL:2011 application time

hi. some small issues....

diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index e3ccf6c7f7..6781e55020 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -1560,7 +1560,7 @@ ProcessUtilitySlow(ParseState *pstate,
  true, /* check_rights */
  true, /* check_not_in_use */
  false, /* skip_build */
- false); /* quiet */
+ false); /* quiet */

Is the above part unnecessary?

diff --git a/src/backend/utils/adt/Makefile b/src/backend/utils/adt/Makefile
index 199eae525d..d04c75b398 100644
--- a/src/backend/utils/adt/Makefile
+++ b/src/backend/utils/adt/Makefile
@@ -78,6 +78,7 @@ OBJS = \
  oracle_compat.o \
  orderedsetaggs.o \
  partitionfuncs.o \
+ period.o \
  pg_locale.o \
  pg_lsn.o \
  pg_upgrade_support.o \
diff --git a/src/backend/utils/adt/period.c b/src/backend/utils/adt/period.c
new file mode 100644
index 0000000000..0ed4304e16
--- /dev/null
+++ b/src/backend/utils/adt/period.c
@@ -0,0 +1,56 @@
+/*-------------------------------------------------------------------------
+ *
+ * period.c
+ *   Functions to support periods.
+ *
+ *
+ * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *   src/backend/utils/adt/period.c
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include "executor/tuptable.h"
+#include "fmgr.h"
+#include "nodes/primnodes.h"
+#include "utils/fmgrprotos.h"
+#include "utils/period.h"
+#include "utils/rangetypes.h"
+
+Datum period_to_range(TupleTableSlot *slot, int startattno, int
endattno, Oid rangetype)
+{
+ Datum startvalue;
+ Datum endvalue;
+ Datum result;
+ bool startisnull;
+ bool endisnull;
+ LOCAL_FCINFO(fcinfo, 2);
+ FmgrInfo flinfo;
+ FuncExpr   *f;
+
+ InitFunctionCallInfoData(*fcinfo, &flinfo, 2, InvalidOid, NULL, NULL);
+ f = makeNode(FuncExpr);
+ f->funcresulttype = rangetype;
+ flinfo.fn_expr = (Node *) f;
+ flinfo.fn_extra = NULL;
+
+ /* compute oldvalue */
+ startvalue = slot_getattr(slot, startattno, &startisnull);
+ endvalue = slot_getattr(slot, endattno, &endisnull);
+
+ fcinfo->args[0].value = startvalue;
+ fcinfo->args[0].isnull = startisnull;
+ fcinfo->args[1].value = endvalue;
+ fcinfo->args[1].isnull = endisnull;
+
+ result = range_constructor2(fcinfo);
+ if (fcinfo->isnull)
+ elog(ERROR, "function %u returned NULL", flinfo.fn_oid);
+
+ return result;
+}

I am confused. so now I only apply v19, 0001 to 0003.
period_to_range function never used. maybe we can move this part to
0005-Add PERIODs.patch?
Also you add change in Makefile in 0003, meson.build change in 0005,
better put it on in 0005?

diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 5b110ca7fe..d54d84adf6 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y

+/*
+ * We need to handle this shift/reduce conflict:
+ * FOR PORTION OF valid_at FROM INTERVAL YEAR TO MONTH TO foo.
+ * This is basically the classic "dangling else" problem, and we want a
+ * similar resolution: treat the TO as part of the INTERVAL, not as part of
+ * the FROM ... TO .... Users can add parentheses if that's a problem.
+ * TO just needs to be higher precedence than YEAR_P etc.
+ * TODO: I need to figure out a %prec solution before this gets committed!
+ */
+%nonassoc YEAR_P MONTH_P DAY_P HOUR_P MINUTE_P
+%nonassoc TO

this part will never happen?
since "FROM INTERVAL YEAR TO MONTH TO"
means "valid_at" will be interval range data type, which does not exist now.

  ri_PerformCheck(riinfo, &qkey, qplan,
  fk_rel, pk_rel,
  oldslot, NULL,
+ targetRangeParam, targetRange,
  true, /* must detect new rows */
  SPI_OK_SELECT);

@@ -905,6 +922,7 @@ RI_FKey_cascade_del(PG_FUNCTION_ARGS)
  ri_PerformCheck(riinfo, &qkey, qplan,
  fk_rel, pk_rel,
  oldslot, NULL,
+ -1, 0,
  true, /* must detect new rows */
  SPI_OK_DELETE);

@@ -1026,6 +1044,7 @@ RI_FKey_cascade_upd(PG_FUNCTION_ARGS)
  ri_PerformCheck(riinfo, &qkey, qplan,
  fk_rel, pk_rel,
  oldslot, newslot,
+ -1, 0,
  true, /* must detect new rows */
  SPI_OK_UPDATE);

@@ -1258,6 +1277,7 @@ ri_set(TriggerData *trigdata, bool is_set_null,
int tgkind)
  ri_PerformCheck(riinfo, &qkey, qplan,
  fk_rel, pk_rel,
  oldslot, NULL,
+ -1, 0,
  true, /* must detect new rows */
  SPI_OK_UPDATE);

@@ -2520,6 +2540,7 @@ ri_PerformCheck(const RI_ConstraintInfo *riinfo,
  RI_QueryKey *qkey, SPIPlanPtr qplan,
  Relation fk_rel, Relation pk_rel,
  TupleTableSlot *oldslot, TupleTableSlot *newslot,
+ int forPortionOfParam, Datum forPortionOf,
  bool detectNewRows, int expect_OK)

for all the refactor related to ri_PerformCheck, do you need (Datum) 0
instead of plain 0?

+  <para>
+   If the table has a range column or
+   <link linkend="ddl-periods-application-periods"><literal>PERIOD</literal></link>,
+   you may supply a <literal>FOR PORTION OF</literal> clause, and
your delete will
+   only affect rows that overlap the given interval. Furthermore, if
a row's span

https://influentialpoints.com/Training/basic_statistics_ranges.htm#:~:text=A%20range%20is%20two%20numbers,or%20the%20difference%20between%20them
So "range" is more accurate than "interval"?

+/* ----------
+ * ForPortionOfState()
+ *
+ * Copies a ForPortionOfState into the current memory context.
+ */
+static ForPortionOfState *
+CopyForPortionOfState(ForPortionOfState *src)
+{
+ ForPortionOfState *dst = NULL;
+ if (src) {
+ MemoryContext oldctx;
+ RangeType *r;
+ TypeCacheEntry *typcache;
+
+ /*
+ * Need to lift the FOR PORTION OF details into a higher memory context
+ * because cascading foreign key update/deletes can cause triggers to fire
+ * triggers, and the AfterTriggerEvents will outlive the FPO
+ * details of the original query.
+ */
+ oldctx = MemoryContextSwitchTo(TopTransactionContext);

should it be "Copy a ForPortionOfState into the TopTransactionContext"?