On 23 August 2016 at 22:18, Robert Haas <robertmh...@gmail.com> wrote:
> On Mon, Aug 22, 2016 at 8:55 PM, Craig Ringer <cr...@2ndquadrant.com>
> wrote:
> > Updated patch series attached. As before, 0-4 intended for commit, 5 just
> > because it'll be handy to have around for people doing wraparound related
> > testing.
> >
> > Again, thanks for taking a look.
>
> /me reviews a bit more deeply.
>
> In 0001, it seems to me that "in-progress" should be "in progress".
>
Fine by me. I was on the fence about it anyway.
+CREATE TYPE txid_status AS ENUM ('committed', 'in-progress', 'aborted');
>
> I'm not really that keen on this approach. I don't think we need to
> introduce a new data type for this, and I would rather not use SQL,
> either. It would be faster and simpler to just return the appropriate
> string from a C function defined directly.
>
Also fine by me. You're right, keep it simple. It means the potential set
of values isn't discoverable the same way, but ... meh. Using it usefully
means reading the docs anyway.
The remaining 2 patches of interest are attached - txid_status() and
txid_convert_if_recent(). Thanks for committing txid_current_if_assigned().
Now I'd best stop pretending I'm in a sensible timezone.
--
Craig Ringer http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services
From 737fe0a0f8e76fc24c19e2e56a2890ff56f37075 Mon Sep 17 00:00:00 2001
From: Craig Ringer <cr...@2ndquadrant.com>
Date: Fri, 19 Aug 2016 14:44:15 +0800
Subject: [PATCH 1/3] Introduce txid_status(bigint) to get status of an xact
If an appliation is disconnected while a COMMIT request is in flight,
the backend crashes mid-commit, etc, then an application may not be
sure whether or not a commit completed successfully or was rolled
back. While two-phase commit solves this it does so at a considerable
overhead, so introduce a lighter alternative.
txid_status(bigint) lets an application determine the status of a
a commit based on an xid-with-epoch as returned by txid_current()
or similar. Status may be committed, aborted, in-progress (including
prepared xacts) or null if the xact is too old for its commit status
to still be retained because it has passed the wrap-around epoch
boundary.
Applications must call txid_current() in their transactions to make
much use of this since PostgreSQL does not automatically report an xid
to the client when one is assigned.
---
doc/src/sgml/func.sgml | 26 ++++++++++++
src/backend/access/transam/clog.c | 23 -----------
src/backend/utils/adt/txid.c | 85 ++++++++++++++++++++++++++++++++++++++
src/include/access/clog.h | 23 +++++++++++
src/include/catalog/pg_proc.h | 2 +
src/include/utils/builtins.h | 1 +
src/test/regress/expected/txid.out | 50 ++++++++++++++++++++++
src/test/regress/sql/txid.sql | 35 ++++++++++++++++
8 files changed, 222 insertions(+), 23 deletions(-)
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 6355300..420cced 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17143,6 +17143,10 @@ SELECT collation for ('foo' COLLATE "de_DE");
<primary>txid_visible_in_snapshot</primary>
</indexterm>
+ <indexterm>
+ <primary>txid_status</primary>
+ </indexterm>
+
<para>
The functions shown in <xref linkend="functions-txid-snapshot">
provide server transaction information in an exportable form. The main
@@ -17193,6 +17197,11 @@ SELECT collation for ('foo' COLLATE "de_DE");
<entry><type>boolean</type></entry>
<entry>is transaction ID visible in snapshot? (do not use with subtransaction ids)</entry>
</row>
+ <row>
+ <entry><literal><function>txid_status(<parameter>bigint</parameter>)</function></literal></entry>
+ <entry><type>txid_status</type></entry>
+ <entry>report the status of the given xact - <literal>committed</literal>, <literal>aborted</literal>, <literal>in progress</literal>, or NULL if the xid is too old</entry>
+ </row>
</tbody>
</tgroup>
</table>
@@ -17263,6 +17272,23 @@ SELECT collation for ('foo' COLLATE "de_DE");
</para>
<para>
+ <function>txid_status(bigint)</> reports the commit status of a recent
+ transaction. Any recent transaction can be identified as one of
+ <itemizedlist>
+ <listitem><para>in progress</></>
+ <listitem><para>committed</></>
+ <listitem><para>aborted</></>
+ </itemizedlist>
+ Prepared transactions are identified as <literal>in progress</>.
+ The commit status of transactions older than the transaction ID wrap-around
+ threshold is no longer known by the system, so <function>txid_status</>
+ returns <literal>NULL</> for such transactions. Applications may use
+ <function>txid_status</> to determine whether a transaction committed
+ or aborted when the application and/or database server crashed or lost
+ connection while a <literal>COMMIT</literal> command was in progress.
+ </para>
+
+ <para>
The functions shown in <xref linkend="functions-commit-timestamp">
provide information about transactions that have been already committed.
These functions mainly provide information about when the transactions
diff --git a/src/backend/access/transam/clog.c b/src/backend/access/transam/clog.c
index 2634476..1a6e26d 100644
--- a/src/backend/access/transam/clog.c
+++ b/src/backend/access/transam/clog.c
@@ -41,29 +41,6 @@
#include "miscadmin.h"
#include "pg_trace.h"
-/*
- * Defines for CLOG page sizes. A page is the same BLCKSZ as is used
- * everywhere else in Postgres.
- *
- * Note: because TransactionIds are 32 bits and wrap around at 0xFFFFFFFF,
- * CLOG page numbering also wraps around at 0xFFFFFFFF/CLOG_XACTS_PER_PAGE,
- * and CLOG segment numbering at
- * 0xFFFFFFFF/CLOG_XACTS_PER_PAGE/SLRU_PAGES_PER_SEGMENT. We need take no
- * explicit notice of that fact in this module, except when comparing segment
- * and page numbers in TruncateCLOG (see CLOGPagePrecedes).
- */
-
-/* We need two bits per xact, so four xacts fit in a byte */
-#define CLOG_BITS_PER_XACT 2
-#define CLOG_XACTS_PER_BYTE 4
-#define CLOG_XACTS_PER_PAGE (BLCKSZ * CLOG_XACTS_PER_BYTE)
-#define CLOG_XACT_BITMASK ((1 << CLOG_BITS_PER_XACT) - 1)
-
-#define TransactionIdToPage(xid) ((xid) / (TransactionId) CLOG_XACTS_PER_PAGE)
-#define TransactionIdToPgIndex(xid) ((xid) % (TransactionId) CLOG_XACTS_PER_PAGE)
-#define TransactionIdToByte(xid) (TransactionIdToPgIndex(xid) / CLOG_XACTS_PER_BYTE)
-#define TransactionIdToBIndex(xid) ((xid) % (TransactionId) CLOG_XACTS_PER_BYTE)
-
/* We store the latest async LSN for each group of transactions */
#define CLOG_XACTS_PER_LSN_GROUP 32 /* keep this a power of 2 */
#define CLOG_LSNS_PER_PAGE (CLOG_XACTS_PER_PAGE / CLOG_XACTS_PER_LSN_GROUP)
diff --git a/src/backend/utils/adt/txid.c b/src/backend/utils/adt/txid.c
index 276075e..70fdffb 100644
--- a/src/backend/utils/adt/txid.c
+++ b/src/backend/utils/adt/txid.c
@@ -21,6 +21,7 @@
#include "postgres.h"
+#include "access/clog.h"
#include "access/transam.h"
#include "access/xact.h"
#include "access/xlog.h"
@@ -117,6 +118,50 @@ convert_xid(TransactionId xid, const TxidEpoch *state)
}
/*
+ * Helper to get a TransactionId from a 64-bit txid with wraparound detection.
+ * ERRORs if the txid is in the future. Returns permanent XIDs unchanged.
+ * Otherwise returns the 32-bit xid and sets the wraparound param to true
+ * if wraparound is detected, false otherwise.
+ */
+static TransactionId
+get_xid_in_recent_past(txid xid_with_epoch, bool *wraparound)
+{
+ uint32 xid_epoch = (uint32)(xid_with_epoch >>32);
+ TransactionId xid = (TransactionId)(xid_with_epoch);
+ TxidEpoch now_epoch;
+
+ load_xid_epoch(&now_epoch);
+
+ *wraparound = false;
+
+ if (!TransactionIdIsNormal(xid))
+ {
+ /* must be a permanent XID, ignore the epoch and return unchanged */
+ return xid;
+ }
+ else if (xid_epoch > now_epoch.epoch
+ || (xid_epoch == now_epoch.epoch && xid > now_epoch.last_xid))
+ {
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("transaction ID "UINT64_FORMAT" is in the future",
+ xid_with_epoch)));
+ }
+ else if (xid_epoch + 1 < now_epoch.epoch
+ || (xid_epoch + 1 == now_epoch.epoch && xid < now_epoch.last_xid))
+ {
+ /* xid too far in the past */
+ *wraparound = true;
+ }
+ else
+ {
+ Assert(TransactionIdPrecedesOrEquals(xid, now_epoch.last_xid));
+ }
+
+ return xid;
+}
+
+/*
* txid comparator for qsort/bsearch
*/
static int
@@ -354,6 +399,9 @@ bad_format:
*
* Return the current toplevel transaction ID as TXID
* If the current transaction does not have one, one is assigned.
+ *
+ * This value has the epoch as the high 32 bits and the 32-bit xid
+ * as the low 32 bits.
*/
Datum
txid_current(PG_FUNCTION_ARGS)
@@ -658,3 +706,40 @@ txid_snapshot_xip(PG_FUNCTION_ARGS)
SRF_RETURN_DONE(fctx);
}
}
+
+/*
+ * Underlying implementation of txid_status, which is mapped to an enum in
+ * system_views.sql.
+ */
+Datum
+txid_status(PG_FUNCTION_ARGS)
+{
+ bool wraparound;
+ uint64 xid_with_epoch = PG_GETARG_INT64(0);
+ TransactionId xid = get_xid_in_recent_past(xid_with_epoch, &wraparound);
+ const char *status;
+
+ if (!TransactionIdIsValid(xid))
+ {
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("transaction ID "UINT64_FORMAT" is an invalid xid",
+ xid_with_epoch)));
+ }
+
+ if (wraparound)
+ PG_RETURN_NULL();
+
+ if (TransactionIdIsCurrentTransactionId(xid) || TransactionIdIsInProgress(xid))
+ status = gettext_noop("in progress");
+ else if (TransactionIdDidCommit(xid))
+ status = gettext_noop("committed");
+ else if (TransactionIdDidAbort(xid))
+ status = gettext_noop("aborted");
+ else
+ /* shouldn't happen */
+ ereport(ERROR,
+ (errmsg_internal("unable to determine commit status of xid "UINT64_FORMAT, xid)));
+
+ PG_RETURN_TEXT_P(cstring_to_text(status));
+}
diff --git a/src/include/access/clog.h b/src/include/access/clog.h
index 06c069a..a763dfb 100644
--- a/src/include/access/clog.h
+++ b/src/include/access/clog.h
@@ -28,6 +28,29 @@ typedef int XidStatus;
#define TRANSACTION_STATUS_ABORTED 0x02
#define TRANSACTION_STATUS_SUB_COMMITTED 0x03
+/*
+ * Defines for CLOG page sizes. A page is the same BLCKSZ as is used
+ * everywhere else in Postgres.
+ *
+ * Note: because TransactionIds are 32 bits and wrap around at 0xFFFFFFFF,
+ * CLOG page numbering also wraps around at 0xFFFFFFFF/CLOG_XACTS_PER_PAGE,
+ * and CLOG segment numbering at
+ * 0xFFFFFFFF/CLOG_XACTS_PER_PAGE/SLRU_PAGES_PER_SEGMENT. We need take no
+ * explicit notice of that fact in this module, except when comparing segment
+ * and page numbers in TruncateCLOG (see CLOGPagePrecedes).
+ */
+
+/* We need two bits per xact, so four xacts fit in a byte */
+#define CLOG_BITS_PER_XACT 2
+#define CLOG_XACTS_PER_BYTE 4
+#define CLOG_XACTS_PER_PAGE (BLCKSZ * CLOG_XACTS_PER_BYTE)
+#define CLOG_XACT_BITMASK ((1 << CLOG_BITS_PER_XACT) - 1)
+
+#define TransactionIdToPage(xid) ((xid) / (TransactionId) CLOG_XACTS_PER_PAGE)
+#define TransactionIdToPgIndex(xid) ((xid) % (TransactionId) CLOG_XACTS_PER_PAGE)
+#define TransactionIdToByte(xid) (TransactionIdToPgIndex(xid) / CLOG_XACTS_PER_BYTE)
+#define TransactionIdToBIndex(xid) ((xid) % (TransactionId) CLOG_XACTS_PER_BYTE)
+
extern void TransactionIdSetTreeStatus(TransactionId xid, int nsubxids,
TransactionId *subxids, XidStatus status, XLogRecPtr lsn);
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 050a98c..472bf4e 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -4916,6 +4916,8 @@ DATA(insert OID = 2947 ( txid_snapshot_xip PGNSP PGUID 12 1 50 0 0 f f f f t
DESCR("get set of in-progress txids in snapshot");
DATA(insert OID = 2948 ( txid_visible_in_snapshot PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 16 "20 2970" _null_ _null_ _null_ _null_ _null_ txid_visible_in_snapshot _null_ _null_ _null_ ));
DESCR("is txid visible in snapshot?");
+DATA(insert OID = 3346 ( txid_status PGNSP PGUID 12 1 0 0 0 f f f f t f v s 1 0 25 "20" _null_ _null_ _null_ _null_ _null_ txid_status _null_ _null_ _null_ ));
+DESCR("commit status of transaction");
/* record comparison using normal comparison rules */
DATA(insert OID = 2981 ( record_eq PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 16 "2249 2249" _null_ _null_ _null_ _null_ _null_ record_eq _null_ _null_ _null_ ));
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
index 2ae212a..baffa38 100644
--- a/src/include/utils/builtins.h
+++ b/src/include/utils/builtins.h
@@ -1227,6 +1227,7 @@ extern Datum txid_snapshot_xmin(PG_FUNCTION_ARGS);
extern Datum txid_snapshot_xmax(PG_FUNCTION_ARGS);
extern Datum txid_snapshot_xip(PG_FUNCTION_ARGS);
extern Datum txid_visible_in_snapshot(PG_FUNCTION_ARGS);
+extern Datum txid_status(PG_FUNCTION_ARGS);
/* uuid.c */
extern Datum uuid_in(PG_FUNCTION_ARGS);
diff --git a/src/test/regress/expected/txid.out b/src/test/regress/expected/txid.out
index 802ccb9..466b7a9 100644
--- a/src/test/regress/expected/txid.out
+++ b/src/test/regress/expected/txid.out
@@ -254,3 +254,53 @@ SELECT txid_current_if_assigned() IS NOT DISTINCT FROM BIGINT :'txid_current';
(1 row)
COMMIT;
+-- test xid status functions
+BEGIN;
+SELECT txid_current() AS committed \gset
+COMMIT;
+BEGIN;
+SELECT txid_current() AS rolledback \gset
+ROLLBACK;
+BEGIN;
+SELECT txid_current() AS inprogress \gset
+SELECT txid_status(:committed) AS committed;
+ committed
+-----------
+ committed
+(1 row)
+
+SELECT txid_status(:rolledback) AS rolledback;
+ rolledback
+------------
+ aborted
+(1 row)
+
+SELECT txid_status(:inprogress) AS inprogress;
+ inprogress
+-------------
+ in progress
+(1 row)
+
+COMMIT;
+BEGIN;
+CREATE FUNCTION test_future_xid_status(bigint)
+RETURNS void
+LANGUAGE plpgsql
+AS
+$$
+BEGIN
+ PERFORM txid_status($1);
+ RAISE EXCEPTION 'didn''t ERROR at xid in the future as expected';
+EXCEPTION
+ WHEN invalid_parameter_value THEN
+ RAISE NOTICE 'Got expected error for xid in the future';
+END;
+$$;
+SELECT test_future_xid_status(:inprogress + 10000);
+NOTICE: Got expected error for xid in the future
+ test_future_xid_status
+------------------------
+
+(1 row)
+
+ROLLBACK;
diff --git a/src/test/regress/sql/txid.sql b/src/test/regress/sql/txid.sql
index 4aefd9e..fb4ef37 100644
--- a/src/test/regress/sql/txid.sql
+++ b/src/test/regress/sql/txid.sql
@@ -59,3 +59,38 @@ SELECT txid_current_if_assigned() IS NULL;
SELECT txid_current() \gset
SELECT txid_current_if_assigned() IS NOT DISTINCT FROM BIGINT :'txid_current';
COMMIT;
+
+-- test xid status functions
+BEGIN;
+SELECT txid_current() AS committed \gset
+COMMIT;
+
+BEGIN;
+SELECT txid_current() AS rolledback \gset
+ROLLBACK;
+
+BEGIN;
+SELECT txid_current() AS inprogress \gset
+
+SELECT txid_status(:committed) AS committed;
+SELECT txid_status(:rolledback) AS rolledback;
+SELECT txid_status(:inprogress) AS inprogress;
+
+COMMIT;
+
+BEGIN;
+CREATE FUNCTION test_future_xid_status(bigint)
+RETURNS void
+LANGUAGE plpgsql
+AS
+$$
+BEGIN
+ PERFORM txid_status($1);
+ RAISE EXCEPTION 'didn''t ERROR at xid in the future as expected';
+EXCEPTION
+ WHEN invalid_parameter_value THEN
+ RAISE NOTICE 'Got expected error for xid in the future';
+END;
+$$;
+SELECT test_future_xid_status(:inprogress + 10000);
+ROLLBACK;
--
2.5.5
From 04ba167c124939e53d92f060ec11a634ca34f7fa Mon Sep 17 00:00:00 2001
From: Craig Ringer <cr...@2ndquadrant.com>
Date: Fri, 19 Aug 2016 14:49:52 +0800
Subject: [PATCH 2/3] Add txid_convert_if_recent() to get the 32-bit xid from a
bigint xid
txid_current() returns an epoch-extended 64-bit xid as a bigint, but
many PostgreSQL functions take and many views report the narrow 32-bit
'xid' type that's subject to wrap-around. To compare these apps must
currently bit-shift the 64-bit xid down and they have no way to check
the epoch.
Add a function that returns the downshifted xid if it's in the current
epoch, or null if the xid is too far in the past and cannot be
compared with any 'xid' value in the current server epoch.
---
doc/src/sgml/func.sgml | 17 ++++-
src/backend/utils/adt/txid.c | 12 ++++
src/include/catalog/pg_proc.h | 4 +-
src/test/regress/expected/alter_table.out | 4 +-
src/test/regress/expected/txid.out | 100 ++++++++++++++++++++++++++++++
src/test/regress/sql/alter_table.sql | 4 +-
src/test/regress/sql/txid.sql | 51 +++++++++++++++
7 files changed, 184 insertions(+), 8 deletions(-)
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 420cced..8bf3eec 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -17198,6 +17198,11 @@ SELECT collation for ('foo' COLLATE "de_DE");
<entry>is transaction ID visible in snapshot? (do not use with subtransaction ids)</entry>
</row>
<row>
+ <entry><literal><function>txid_convert_if_recent(<parameter>bigint</parameter>)</function></literal></entry>
+ <entry><type>xid</type></entry>
+ <entry>return the 32-bit <type>xid</> for a 64-bit transaction ID if it isn't wrapped around, otherwise return null</entry>
+ </row>
+ <row>
<entry><literal><function>txid_status(<parameter>bigint</parameter>)</function></literal></entry>
<entry><type>txid_status</type></entry>
<entry>report the status of the given xact - <literal>committed</literal>, <literal>aborted</literal>, <literal>in progress</literal>, or NULL if the xid is too old</entry>
@@ -17210,9 +17215,15 @@ SELECT collation for ('foo' COLLATE "de_DE");
The internal transaction ID type (<type>xid</>) is 32 bits wide and
wraps around every 4 billion transactions. However, these functions
export a 64-bit format that is extended with an <quote>epoch</> counter
- so it will not wrap around during the life of an installation.
- The data type used by these functions, <type>txid_snapshot</type>,
- stores information about transaction ID
+ so it will not wrap around during the life of an installation. For that
+ reason you cannot cast a bigint transaction ID directly to <type>xid</>
+ and must use <function>txid_convert_if_recent(bigint)</function> instead of
+ casting to <type>xid</>.
+ </para>
+
+ <para>
+ The data type used by the xid snapshot functions,
+ <type>txid_snapshot</type>, stores information about transaction ID
visibility at a particular moment in time. Its components are
described in <xref linkend="functions-txid-snapshot-parts">.
</para>
diff --git a/src/backend/utils/adt/txid.c b/src/backend/utils/adt/txid.c
index 70fdffb..2f1b614 100644
--- a/src/backend/utils/adt/txid.c
+++ b/src/backend/utils/adt/txid.c
@@ -707,6 +707,18 @@ txid_snapshot_xip(PG_FUNCTION_ARGS)
}
}
+Datum
+txid_convert_if_recent(PG_FUNCTION_ARGS)
+{
+ bool wraparound;
+ TransactionId xid = get_xid_in_recent_past(PG_GETARG_INT64(0), &wraparound);
+
+ if (wraparound)
+ PG_RETURN_NULL();
+ else
+ return TransactionIdGetDatum(xid);
+}
+
/*
* Underlying implementation of txid_status, which is mapped to an enum in
* system_views.sql.
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 472bf4e..1873893 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -4916,8 +4916,10 @@ DATA(insert OID = 2947 ( txid_snapshot_xip PGNSP PGUID 12 1 50 0 0 f f f f t
DESCR("get set of in-progress txids in snapshot");
DATA(insert OID = 2948 ( txid_visible_in_snapshot PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 16 "20 2970" _null_ _null_ _null_ _null_ _null_ txid_visible_in_snapshot _null_ _null_ _null_ ));
DESCR("is txid visible in snapshot?");
-DATA(insert OID = 3346 ( txid_status PGNSP PGUID 12 1 0 0 0 f f f f t f v s 1 0 25 "20" _null_ _null_ _null_ _null_ _null_ txid_status _null_ _null_ _null_ ));
+DATA(insert OID = 3347 ( txid_status PGNSP PGUID 12 1 0 0 0 f f f f t f v s 1 0 25 "20" _null_ _null_ _null_ _null_ _null_ txid_status _null_ _null_ _null_ ));
DESCR("commit status of transaction");
+DATA(insert OID = 3344 ( txid_convert_if_recent PGNSP PGUID 12 1 0 0 0 f f f f t f v s 1 0 28 "20" _null_ _null_ _null_ _null_ _null_ txid_convert_if_recent _null_ _null_ _null_ ));
+DESCR("get the xid from a bigint transaction id if not wrapped around");
/* record comparison using normal comparison rules */
DATA(insert OID = 2981 ( record_eq PGNSP PGUID 12 1 0 0 0 f f f f t f i s 2 0 16 "2249 2249" _null_ _null_ _null_ _null_ _null_ record_eq _null_ _null_ _null_ ));
diff --git a/src/test/regress/expected/alter_table.out b/src/test/regress/expected/alter_table.out
index 3232cda..3bdbb87 100644
--- a/src/test/regress/expected/alter_table.out
+++ b/src/test/regress/expected/alter_table.out
@@ -2029,7 +2029,7 @@ from pg_locks l join pg_class c on l.relation = c.oid
where virtualtransaction = (
select virtualtransaction
from pg_locks
- where transactionid = txid_current()::integer)
+ where transactionid is not distinct from txid_convert_if_recent(txid_current()) )
and locktype = 'relation'
and relnamespace != (select oid from pg_namespace where nspname = 'pg_catalog')
and c.relname != 'my_locks'
@@ -2192,7 +2192,7 @@ from pg_locks l join pg_class c on l.relation = c.oid
where virtualtransaction = (
select virtualtransaction
from pg_locks
- where transactionid = txid_current()::integer)
+ where transactionid is not distinct from txid_convert_if_recent(txid_current()) )
and locktype = 'relation'
and relnamespace != (select oid from pg_namespace where nspname = 'pg_catalog')
and c.relname = 'my_locks'
diff --git a/src/test/regress/expected/txid.out b/src/test/regress/expected/txid.out
index 466b7a9..5dee554 100644
--- a/src/test/regress/expected/txid.out
+++ b/src/test/regress/expected/txid.out
@@ -263,6 +263,63 @@ SELECT txid_current() AS rolledback \gset
ROLLBACK;
BEGIN;
SELECT txid_current() AS inprogress \gset
+-- We can reasonably assume we haven't hit the first xid
+-- wraparound here, so:
+SELECT txid_convert_if_recent(:committed) = :'committed'::xid;
+ ?column?
+----------
+ t
+(1 row)
+
+SELECT txid_convert_if_recent(:rolledback) = :'rolledback'::xid;
+ ?column?
+----------
+ t
+(1 row)
+
+SELECT txid_convert_if_recent(:inprogress) = :'inprogress'::xid;
+ ?column?
+----------
+ t
+(1 row)
+
+SELECT txid_convert_if_recent(0) = '0'::xid; -- InvalidTransactionId
+ ?column?
+----------
+ t
+(1 row)
+
+SELECT txid_convert_if_recent(1) = '1'::xid; -- BootstrapTransactionId
+ ?column?
+----------
+ t
+(1 row)
+
+SELECT txid_convert_if_recent(2) = '2'::xid; -- FrozenTransactionId
+ ?column?
+----------
+ t
+(1 row)
+
+-- we ignore epoch for the fixed xids
+SELECT txid_convert_if_recent(BIGINT '1' << 32);
+ txid_convert_if_recent
+------------------------
+ 0
+(1 row)
+
+SELECT txid_convert_if_recent((BIGINT '1' << 32) + 1);
+ txid_convert_if_recent
+------------------------
+ 1
+(1 row)
+
+SELECT txid_convert_if_recent((BIGINT '1' << 32) + 2);
+ txid_convert_if_recent
+------------------------
+ 2
+(1 row)
+
SELECT txid_status(:committed) AS committed;
committed
-----------
@@ -282,6 +339,49 @@ SELECT txid_status(:inprogress) AS inprogress;
(1 row)
COMMIT;
+-- Check xids in the future
+DO
+$$
+BEGIN
+ PERFORM txid_convert_if_recent(txid_current() + (BIGINT '1' << 32));
+EXCEPTION
+ WHEN invalid_parameter_value THEN
+ RAISE NOTICE 'got expected xid out of range error';
+END;
+$$;
+NOTICE: got expected xid out of range error
+DO
+$$
+BEGIN
+ PERFORM txid_convert_if_recent((BIGINT '1' << 32) - 1);
+EXCEPTION
+ WHEN invalid_parameter_value THEN
+ RAISE NOTICE 'got expected xid out of range error';
+END;
+$$;
+NOTICE: got expected xid out of range error
+BEGIN;
+CREATE FUNCTION test_future_xid(bigint)
+RETURNS void
+LANGUAGE plpgsql
+AS
+$$
+BEGIN
+ PERFORM txid_convert_if_recent($1);
+ RAISE EXCEPTION 'didn''t ERROR at xid in the future as expected';
+EXCEPTION
+ WHEN invalid_parameter_value THEN
+ RAISE NOTICE 'Got expected error for xid in the future';
+END;
+$$;
+SELECT test_future_xid(:inprogress + 100000);
+NOTICE: Got expected error for xid in the future
+ test_future_xid
+-----------------
+
+(1 row)
+
+ROLLBACK;
BEGIN;
CREATE FUNCTION test_future_xid_status(bigint)
RETURNS void
diff --git a/src/test/regress/sql/alter_table.sql b/src/test/regress/sql/alter_table.sql
index 72e65d4..124d71f 100644
--- a/src/test/regress/sql/alter_table.sql
+++ b/src/test/regress/sql/alter_table.sql
@@ -1335,7 +1335,7 @@ from pg_locks l join pg_class c on l.relation = c.oid
where virtualtransaction = (
select virtualtransaction
from pg_locks
- where transactionid = txid_current()::integer)
+ where transactionid is not distinct from txid_convert_if_recent(txid_current()) )
and locktype = 'relation'
and relnamespace != (select oid from pg_namespace where nspname = 'pg_catalog')
and c.relname != 'my_locks'
@@ -1422,7 +1422,7 @@ from pg_locks l join pg_class c on l.relation = c.oid
where virtualtransaction = (
select virtualtransaction
from pg_locks
- where transactionid = txid_current()::integer)
+ where transactionid is not distinct from txid_convert_if_recent(txid_current()) )
and locktype = 'relation'
and relnamespace != (select oid from pg_namespace where nspname = 'pg_catalog')
and c.relname = 'my_locks'
diff --git a/src/test/regress/sql/txid.sql b/src/test/regress/sql/txid.sql
index fb4ef37..2d451e6 100644
--- a/src/test/regress/sql/txid.sql
+++ b/src/test/regress/sql/txid.sql
@@ -72,12 +72,63 @@ ROLLBACK;
BEGIN;
SELECT txid_current() AS inprogress \gset
+-- We can reasonably assume we haven't hit the first xid
+-- wraparound here, so:
+SELECT txid_convert_if_recent(:committed) = :'committed'::xid;
+SELECT txid_convert_if_recent(:rolledback) = :'rolledback'::xid;
+SELECT txid_convert_if_recent(:inprogress) = :'inprogress'::xid;
+SELECT txid_convert_if_recent(0) = '0'::xid; -- InvalidTransactionId
+SELECT txid_convert_if_recent(1) = '1'::xid; -- BootstrapTransactionId
+SELECT txid_convert_if_recent(2) = '2'::xid; -- FrozenTransactionId
+-- we ignore epoch for the fixed xids
+SELECT txid_convert_if_recent(BIGINT '1' << 32);
+SELECT txid_convert_if_recent((BIGINT '1' << 32) + 1);
+SELECT txid_convert_if_recent((BIGINT '1' << 32) + 2);
+
SELECT txid_status(:committed) AS committed;
SELECT txid_status(:rolledback) AS rolledback;
SELECT txid_status(:inprogress) AS inprogress;
COMMIT;
+-- Check xids in the future
+DO
+$$
+BEGIN
+ PERFORM txid_convert_if_recent(txid_current() + (BIGINT '1' << 32));
+EXCEPTION
+ WHEN invalid_parameter_value THEN
+ RAISE NOTICE 'got expected xid out of range error';
+END;
+$$;
+
+DO
+$$
+BEGIN
+ PERFORM txid_convert_if_recent((BIGINT '1' << 32) - 1);
+EXCEPTION
+ WHEN invalid_parameter_value THEN
+ RAISE NOTICE 'got expected xid out of range error';
+END;
+$$;
+
+BEGIN;
+CREATE FUNCTION test_future_xid(bigint)
+RETURNS void
+LANGUAGE plpgsql
+AS
+$$
+BEGIN
+ PERFORM txid_convert_if_recent($1);
+ RAISE EXCEPTION 'didn''t ERROR at xid in the future as expected';
+EXCEPTION
+ WHEN invalid_parameter_value THEN
+ RAISE NOTICE 'Got expected error for xid in the future';
+END;
+$$;
+SELECT test_future_xid(:inprogress + 100000);
+ROLLBACK;
+
BEGIN;
CREATE FUNCTION test_future_xid_status(bigint)
RETURNS void
--
2.5.5
--
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