diff --git a/doc/src/sgml/perform.sgml b/doc/src/sgml/perform.sgml
index 262f30fd4c..eb0bbe4657 100644
--- a/doc/src/sgml/perform.sgml
+++ b/doc/src/sgml/perform.sgml
@@ -1534,9 +1534,10 @@ SELECT * FROM x, y, a, b, c WHERE something AND somethingelse;
TRUNCATE command. In such cases no WAL
needs to be written, because in case of an error, the files
containing the newly loaded data will be removed anyway.
- However, this consideration only applies when
- is minimal as all commands
- must write WAL otherwise.
+ However, this consideration only applies for non-partitioned
+ tables when is
+ minimal as all commands must write WAL
+ otherwise.
diff --git a/doc/src/sgml/ref/copy.sgml b/doc/src/sgml/ref/copy.sgml
index 13a8b68d95..8c930d554f 100644
--- a/doc/src/sgml/ref/copy.sgml
+++ b/doc/src/sgml/ref/copy.sgml
@@ -222,9 +222,10 @@ COPY { table_name [ ( VACUUM FREEZE command.
This is intended as a performance option for initial data loading.
- Rows will be frozen only if the table being loaded has been created
- or truncated in the current subtransaction, there are no cursors
- open and there are no older snapshots held by this transaction.
+ Rows will be frozen only for non-partitioned tables if the table
+ being loaded has been created or truncated in the current
+ subtransaction, there are no cursors open and there are no older
+ snapshots held by this transaction.
Note that all other sessions will immediately be able to see the data
diff --git a/src/backend/commands/copy.c b/src/backend/commands/copy.c
index d06662bd32..6eae1f029b 100644
--- a/src/backend/commands/copy.c
+++ b/src/backend/commands/copy.c
@@ -2414,11 +2414,20 @@ CopyFrom(CopyState cstate)
* go into pages containing tuples from any other transactions --- but this
* must be the case if we have a new table or new relfilenode, so we need
* no additional work to enforce that.
+ *
+ * We currently don't support this optimization if the COPY target is a
+ * partitioned table as we currently only lazily initialize partition
+ * information when routing the first tuple to the partition. We cannot
+ * know at this stage if we can perform this optimization. It should be
+ * possible to improve on this, but it does mean maintaining heap insert
+ * option flags per partition and setting them when we first open the
+ * partition.
*----------
*/
/* createSubid is creation check, newRelfilenodeSubid is truncation check */
- if (cstate->rel->rd_createSubid != InvalidSubTransactionId ||
- cstate->rel->rd_newRelfilenodeSubid != InvalidSubTransactionId)
+ if (cstate->rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE &&
+ (cstate->rel->rd_createSubid != InvalidSubTransactionId ||
+ cstate->rel->rd_newRelfilenodeSubid != InvalidSubTransactionId))
{
hi_options |= HEAP_INSERT_SKIP_FSM;
if (!XLogIsNeeded())
@@ -2438,6 +2447,22 @@ CopyFrom(CopyState cstate)
*/
if (cstate->freeze)
{
+ /*
+ * We currently disallow COPY FREEZE on partitioned tables. The
+ * reason for this is that we've simply not yet opened the partitions
+ * to determine if the optimization can be applied to them. We could
+ * go and open them all here, but doing so may be quite a costly
+ * overhead for small copies. In any case, we may just end up routing
+ * tuples to a small number of partitions. It seems better just to
+ * raise an ERROR for partitioned tables.
+ */
+ if (cstate->rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
+ {
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("cannot perform FREEZE on a partitioned table")));
+ }
+
/*
* Tolerate one registration for the benefit of FirstXactSnapshot.
* Scan-bearing queries generally create at least two registrations,
diff --git a/src/test/regress/input/copy.source b/src/test/regress/input/copy.source
index 014b1b5711..b5a6a6a4b9 100644
--- a/src/test/regress/input/copy.source
+++ b/src/test/regress/input/copy.source
@@ -159,6 +159,12 @@ truncate parted_copytest;
copy parted_copytest from '@abs_builddir@/results/parted_copytest.csv';
+-- Ensure COPY FREEZE errors for partitioned tables.
+begin;
+truncate parted_copytest;
+copy parted_copytest from '@abs_builddir@/results/parted_copytest.csv' (freeze);
+rollback;
+
select tableoid::regclass,count(*),sum(a) from parted_copytest
group by tableoid order by tableoid::regclass::name;
diff --git a/src/test/regress/output/copy.source b/src/test/regress/output/copy.source
index ab096153ad..c4f10a223a 100644
--- a/src/test/regress/output/copy.source
+++ b/src/test/regress/output/copy.source
@@ -113,6 +113,12 @@ insert into parted_copytest select x,1,'One' from generate_series(1011,1020) x;
copy (select * from parted_copytest order by a) to '@abs_builddir@/results/parted_copytest.csv';
truncate parted_copytest;
copy parted_copytest from '@abs_builddir@/results/parted_copytest.csv';
+-- Ensure COPY FREEZE errors for partitioned tables.
+begin;
+truncate parted_copytest;
+copy parted_copytest from '@abs_builddir@/results/parted_copytest.csv' (freeze);
+ERROR: cannot perform FREEZE on a partitioned table
+rollback;
select tableoid::regclass,count(*),sum(a) from parted_copytest
group by tableoid order by tableoid::regclass::name;
tableoid | count | sum