diff options
Diffstat (limited to 'src/backend')
| -rw-r--r-- | src/backend/access/heap/heapam.c | 17 | ||||
| -rw-r--r-- | src/backend/commands/copy.c | 33 | ||||
| -rw-r--r-- | src/backend/parser/gram.y | 4 | ||||
| -rw-r--r-- | src/backend/utils/mmgr/portalmem.c | 19 | ||||
| -rw-r--r-- | src/backend/utils/time/snapmgr.c | 9 |
5 files changed, 81 insertions, 1 deletions
diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c index 4abbdb68468..b66e26bebff 100644 --- a/src/backend/access/heap/heapam.c +++ b/src/backend/access/heap/heapam.c @@ -1875,6 +1875,14 @@ FreeBulkInsertState(BulkInsertState bistate) * The HEAP_INSERT_SKIP_FSM option is passed directly to * RelationGetBufferForTuple, which see for more info. * + * HEAP_INSERT_COMMITTED should only be specified for inserts into + * relfilenodes created during the current subtransaction and when + * there are no prior snapshots or pre-existing portals open. + * + * HEAP_INSERT_FROZEN only has meaning when HEAP_INSERT_COMMITTED is + * also set. This causes rows to be frozen, which is an MVCC violation + * and requires explicit options chosen by user. + * * Note that these options will be applied when inserting into the heap's * TOAST table, too, if the tuple requires any out-of-line data. * @@ -2078,7 +2086,14 @@ heap_prepare_insert(Relation relation, HeapTuple tup, TransactionId xid, tup->t_data->t_infomask &= ~(HEAP_XACT_MASK); tup->t_data->t_infomask2 &= ~(HEAP2_XACT_MASK); tup->t_data->t_infomask |= HEAP_XMAX_INVALID; - HeapTupleHeaderSetXmin(tup->t_data, xid); + if (options & HEAP_INSERT_COMMITTED) + { + tup->t_data->t_infomask |= HEAP_XMIN_COMMITTED; + if (options & HEAP_INSERT_FROZEN) + HeapTupleHeaderSetXmin(tup->t_data, FrozenTransactionId); + } + else + HeapTupleHeaderSetXmin(tup->t_data, xid); HeapTupleHeaderSetCmin(tup->t_data, cid); HeapTupleHeaderSetXmax(tup->t_data, 0); /* for cleanliness */ tup->t_tableOid = RelationGetRelid(relation); diff --git a/src/backend/commands/copy.c b/src/backend/commands/copy.c index 10c89c79b91..479c4cb17d6 100644 --- a/src/backend/commands/copy.c +++ b/src/backend/commands/copy.c @@ -44,6 +44,7 @@ #include "utils/builtins.h" #include "utils/lsyscache.h" #include "utils/memutils.h" +#include "utils/portal.h" #include "utils/rel.h" #include "utils/snapmgr.h" @@ -109,6 +110,7 @@ typedef struct CopyStateData char *filename; /* filename, or NULL for STDIN/STDOUT */ bool binary; /* binary format? */ bool oids; /* include OIDs? */ + bool freeze; /* freeze rows on loading? */ bool csv_mode; /* Comma Separated Value format? */ bool header_line; /* CSV header line? */ char *null_print; /* NULL marker string (server encoding!) */ @@ -895,6 +897,14 @@ ProcessCopyOptions(CopyState cstate, errmsg("conflicting or redundant options"))); cstate->oids = defGetBoolean(defel); } + else if (strcmp(defel->defname, "freeze") == 0) + { + if (cstate->freeze) + ereport(ERROR, + (errcode(ERRCODE_SYNTAX_ERROR), + errmsg("conflicting or redundant options"))); + cstate->freeze = defGetBoolean(defel); + } else if (strcmp(defel->defname, "delimiter") == 0) { if (cstate->delim) @@ -1974,8 +1984,31 @@ CopyFrom(CopyState cstate) hi_options |= HEAP_INSERT_SKIP_FSM; if (!XLogIsNeeded()) hi_options |= HEAP_INSERT_SKIP_WAL; + + /* + * Optimize if new relfilenode was created in this subxact or + * one of its committed children and we won't see those rows later + * as part of an earlier scan or command. This ensures that if this + * subtransaction aborts then the frozen rows won't be visible + * after xact cleanup. Note that the stronger test of exactly + * which subtransaction created it is crucial for correctness + * of this optimisation. + */ + if (ThereAreNoPriorRegisteredSnapshots() && + ThereAreNoReadyPortals() && + cstate->rel->rd_newRelfilenodeSubid == GetCurrentSubTransactionId()) + { + hi_options |= HEAP_INSERT_COMMITTED; + if (cstate->freeze) + hi_options |= HEAP_INSERT_FROZEN; + } } + if (cstate->freeze && (hi_options & HEAP_INSERT_FROZEN) == 0) + ereport(NOTICE, + (errcode(ERRCODE_INVALID_PARAMETER_VALUE), + errmsg("FREEZE option specified but pre-conditions not met"))); + /* * We need a ResultRelInfo so we can use the regular executor's * index-entry-making machinery. (There used to be a huge amount of code diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y index e4ff76e66e0..ad98b364f13 100644 --- a/src/backend/parser/gram.y +++ b/src/backend/parser/gram.y @@ -2383,6 +2383,10 @@ copy_opt_item: { $$ = makeDefElem("oids", (Node *)makeInteger(TRUE)); } + | FREEZE + { + $$ = makeDefElem("freeze", (Node *)makeInteger(TRUE)); + } | DELIMITER opt_as Sconst { $$ = makeDefElem("delimiter", (Node *)makeString($3)); diff --git a/src/backend/utils/mmgr/portalmem.c b/src/backend/utils/mmgr/portalmem.c index 5713bbe12ce..b981f975af5 100644 --- a/src/backend/utils/mmgr/portalmem.c +++ b/src/backend/utils/mmgr/portalmem.c @@ -1055,3 +1055,22 @@ pg_cursor(PG_FUNCTION_ARGS) return (Datum) 0; } + +bool +ThereAreNoReadyPortals(void) +{ + HASH_SEQ_STATUS status; + PortalHashEnt *hentry; + + hash_seq_init(&status, PortalHashTable); + + while ((hentry = (PortalHashEnt *) hash_seq_search(&status)) != NULL) + { + Portal portal = hentry->portal; + + if (portal->status == PORTAL_READY) + return false; + } + + return true; +} diff --git a/src/backend/utils/time/snapmgr.c b/src/backend/utils/time/snapmgr.c index fa514f6b48f..5705a2d75e9 100644 --- a/src/backend/utils/time/snapmgr.c +++ b/src/backend/utils/time/snapmgr.c @@ -1184,3 +1184,12 @@ DeleteAllExportedSnapshotFiles(void) FreeDir(s_dir); } + +bool +ThereAreNoPriorRegisteredSnapshots(void) +{ + if (RegisteredSnapshots <= 1) + return true; + + return false; +} |