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Add decoding of sequences to built-in replication

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This commit adds support for decoding of sequences to the built-in
replication (the infrastructure was added by commit 0da92dc530).

The syntax and behavior mostly mimics handling of tables, i.e. a
publication may be defined as FOR ALL SEQUENCES (replicating all
sequences in a database), FOR ALL SEQUENCES IN SCHEMA (replicating
all sequences in a particular schema) or individual sequences.

To publish sequence modifications, the publication has to include
'sequence' action. The protocol is extended with a new message,
describing sequence increments.

A new system view pg_publication_sequences lists all the sequences
added to a publication, both directly and indirectly. Various psql
commands (\d and \dRp) are improved to also display publications
including a given sequence, or sequences included in a publication.

Author: Tomas Vondra, Cary Huang
Reviewed-by: Peter Eisentraut, Amit Kapila, Hannu Krosing, Andres
             Freund, Petr Jelinek
Discussion: https://postgr.es/m/d045f3c2-6cfb-06d3-5540-e63c320df8bc@enterprisedb.com
Discussion: https://postgr.es/m/1710ed7e13b.cd7177461430746.3372264562543607781@highgo.ca
This commit is contained in:
Tomas Vondra
2022-03-24 18:20:21 +01:00
parent 0adb3dc68b
commit 75b1521dae
40 changed files with 3236 additions and 469 deletions
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109
src/backend/replication/logical/tablesync.c
View File

@ -100,6 +100,7 @@
#include "catalog/pg_subscription_rel.h"
#include "catalog/pg_type.h"
#include "commands/copy.h"
#include "commands/sequence.h"
#include "miscadmin.h"
#include "parser/parse_relation.h"
#include "pgstat.h"
@ -999,6 +1000,95 @@ copy_table(Relation rel)
logicalrep_rel_close(relmapentry, NoLock);
}
/*
* Fetch sequence data (current state) from the remote node.
*/
static void
fetch_sequence_data(char *nspname, char *relname,
int64 *last_value, int64 *log_cnt, bool *is_called)
{
WalRcvExecResult *res;
StringInfoData cmd;
TupleTableSlot *slot;
Oid tableRow[3] = {INT8OID, INT8OID, BOOLOID};
initStringInfo(&cmd);
appendStringInfo(&cmd, "SELECT last_value, log_cnt, is_called\n"
" FROM %s", quote_qualified_identifier(nspname, relname));
res = walrcv_exec(LogRepWorkerWalRcvConn, cmd.data, 3, tableRow);
pfree(cmd.data);
if (res->status != WALRCV_OK_TUPLES)
ereport(ERROR,
(errmsg("could not receive list of replicated tables from the publisher: %s",
res->err)));
/* Process the sequence. */
slot = MakeSingleTupleTableSlot(res->tupledesc, &TTSOpsMinimalTuple);
while (tuplestore_gettupleslot(res->tuplestore, true, false, slot))
{
bool isnull;
*last_value = DatumGetInt64(slot_getattr(slot, 1, &isnull));
Assert(!isnull);
*log_cnt = DatumGetInt64(slot_getattr(slot, 2, &isnull));
Assert(!isnull);
*is_called = DatumGetBool(slot_getattr(slot, 3, &isnull));
Assert(!isnull);
ExecClearTuple(slot);
}
ExecDropSingleTupleTableSlot(slot);
walrcv_clear_result(res);
}
/*
* Copy existing data of a sequence from publisher.
*
* Caller is responsible for locking the local relation.
*/
static void
copy_sequence(Relation rel)
{
LogicalRepRelMapEntry *relmapentry;
LogicalRepRelation lrel;
List *qual = NIL;
StringInfoData cmd;
int64 last_value = 0,
log_cnt = 0;
bool is_called = 0;
/* Get the publisher relation info. */
fetch_remote_table_info(get_namespace_name(RelationGetNamespace(rel)),
RelationGetRelationName(rel), &lrel, &qual);
/* sequences don't have row filters */
Assert(!qual);
/* Put the relation into relmap. */
logicalrep_relmap_update(&lrel);
/* Map the publisher relation to local one. */
relmapentry = logicalrep_rel_open(lrel.remoteid, NoLock);
Assert(rel == relmapentry->localrel);
/* Start copy on the publisher. */
initStringInfo(&cmd);
Assert(lrel.relkind == RELKIND_SEQUENCE);
fetch_sequence_data(lrel.nspname, lrel.relname, &last_value, &log_cnt, &is_called);
/* tablesync sets the sequences in non-transactional way */
SetSequence(RelationGetRelid(rel), false, last_value, log_cnt, is_called);
logicalrep_rel_close(relmapentry, NoLock);
}
/*
* Determine the tablesync slot name.
*
@ -1260,10 +1350,21 @@ LogicalRepSyncTableStart(XLogRecPtr *origin_startpos)
originname)));
}
/* Now do the initial data copy */
PushActiveSnapshot(GetTransactionSnapshot());
copy_table(rel);
PopActiveSnapshot();
/* Do the right action depending on the relation kind. */
if (get_rel_relkind(RelationGetRelid(rel)) == RELKIND_SEQUENCE)
{
/* Now do the initial sequence copy */
PushActiveSnapshot(GetTransactionSnapshot());
copy_sequence(rel);
PopActiveSnapshot();
}
else
{
/* Now do the initial data copy */
PushActiveSnapshot(GetTransactionSnapshot());
copy_table(rel);
PopActiveSnapshot();
}
res = walrcv_exec(LogRepWorkerWalRcvConn, "COMMIT", 0, NULL);
if (res->status != WALRCV_OK_COMMAND)