Postgres delete replication slot. These slots will be preserved during switchover/failover.

The base name of the shared object containing the output plugin this logical slot Jun 27, 2024 · I'm trying to drop the replication slot. 5 ). Next, promote the intended standby node to a standalone node. For more on replication slots, see Section 25. 6). NULL if inactive. However, one of the very crucial functionalities is still missing in PostgreSQL, which prevents logical replication to be part of critical production Apr 9, 2021 · I am having 3 Node Postgres cluster and want to know tables/databases which are under logical replication. Jun 2, 2023 · Terms. You can customize the solution to meet specific requirements, including Jul 29, 2020 · PostgreSQL version 10 introduced several exciting features and improvements to the existing landscape of PostgreSQL. name. VACUUM cannot remove tuples deleted by any later transaction. The default behavior is that the replication slot remains configured for the connector when the connector stops. PostgreSQL supports both mechanisms concurrently, see Chapter 27. Be careful with orphaned slots. slot_name: name : A unique, cluster-wide identifier for the replication slot: plugin: name : The base name of the shared object containing the output plugin this logical slot is using, or null for physical slots. conf and restart the server. Then drop the slot. PostgreSQL provides infrastructure to stream the modifications performed via SQL to external consumers. I tried to drop logical replication subscription. Monitoring your replication slots is something that you don’t want to miss. 0. They work by storing the LSN of the WAL See full list on hevodata. In the meantime, all you can do is monitor the situation, then then drop the slot if it starts to fall behind too far. conf on the standby server to verify that. Starting from PostgreSQL 9. WAL -> Logical Decoding/output_plugin -> logical log -> sender -> receiver & apply. Sep 19, 2018 · Set "wal_level" back to "archive", and restart. By leveraging Aurora’s cross-account clone and PostgreSQL logical replication, you can achieve near real-time synchronization between a source and a target database in different AWS accounts. Logical replication is a method of replicating data objects and their changes, based upon their replication identity (usually a primary key). To check the maximum number of Limit the size of a slot in PostgreSQL. Streaming Replication Protocol #. To initiate streaming replication, the frontend sends the replication parameter in the startup message. slot_type text. 10. catalog_xmin xid Jan 10, 2024 · To set up logical replication, you must first create a publisher on the source database that defines which tables to publish. This functionality can be used for a variety of purposes, including replication solutions and auditing. – Laurenz Albe. After your test is successful, drop the subscription on the replica using pglogical. Jul 30, 2019 · SELECT pg_drop_replication_slot('slot_name') from pg_replication_slots where active = 'f'; RDS PostgreSQL supports native logical replication based on publication and subscription model. 20. xmin xid. Description. 3,202 1 12 18. I think the justification for this monstrosity is they want to make it really hard to drop a Nov 30, 2022 · I don’t have the data and log files from the original situation any longer, but the following steps are enough to reproduce the issue. This post discusses how to use the existing framework to create a self-managed […] Dec 13, 2021 · Instead of using wal_keep_size=30GB, I suggest you to create a replication slot and set max_slot_wal_keep_size to 40GB. Oct 12, 2022 · Streaming replication is a core utility of PostgreSQL introduced in version 9. 6 and Chapter 49. ) Aug 10, 2021 · 3 Answers. Subscribers. For these scenarios, the following query returns the age of the oldest transaction and the number of transactions left until wraparound: Physical Replication without Slots. DROP SUBSCRIPTION removes a subscription from the database cluster. Then PostgreSQL will call this command and remove an archived WAL segment after it has been restored. However, you might want to remove or comment out replication configurations in postgresql. Verify that the replication slot is also dropped on the primary. To prevent replication slots that fell behind or have been abandoned from breaking your database, you can set the parameter max_slot_wal_keep_size. PostgreSQL won't retain May 2, 2024 · Therefore, monitoring the replication lag and replication slots status is crucial for read replicas. Postgres. Begin #. A Boolean value of true (or on, yes, 1) tells the backend to go into physical replication walsender mode, wherein a small set of replication commands, shown below, can be issued instead of SQL statements. If nothing seems to have happened after changing a setting run a manual CHECKPOINT command. It also supports using logical decoding. pg_recvlogical -h pgserver. These slots will be preserved during switchover/failover. Replication slots are a feature of PostgreSQL, introduced in version 9. Servers will be either a master or a standby server. If you have shell access to the server or superuser privileges, you can do it. Removing a slot requires access to the slot machinery. oid) Jan 11, 2024 · The relationship between publisher and subscriber is mediated by PostgreSQL’s replication slots. false. Just collect the information from view pg_replication_slots in the primary node just like below: Jul 11, 2024 · Physical replication slots were introduced to PostgreSQL with version 9. catalog_xmin xid Jul 11, 2022 · I want to drop the database, but kept getting that I have active replication slot. 49. In this example, I use the wal2json I create the replication slot using Python, as shown in the next few steps. 4. 4, that provide a more robust way to handle data replication between a primary database server and one or more secondary servers (standbys). An “f” in this column indicates that the replication slot is not active, meaning it is not currently being utilized. Feb 3, 2021 · I've an application which use debezium-postgres connector to publish events on kafka from postgres. datoid oid (references pg_database. pg_recvlogical has no equivalent to the logical decoding SQL interface's Jan 23, 2019 · If your replication is working, that would be a sign that it is not using the replication slot. Primaries can send data, while standbys are always Sep 13, 2023 · I don't want to drop the slot though. Laurenz Albe. Streaming Replication Protocol. That depends on what access you have. 55. If you run multiple AWS DMS tasks or you have old tasks that run on the same DB instance, then remove the used replication slots. Feb 9, 2019 · Either a replica is using a slot and is unable to keep up, or you have a slot that has no replica attached, for example, you destroyed the replica but didn't drop the slot it used to occupy. Changes are sent out in streams identified by logical replication slots. (You can use ALTER SUBSCRIPTION to unset the slot. These settings control the behavior of the built-in streaming replication feature (see Section 26. azure. In a cloud setup, often simply terminating the host will solve all this by bringing up a new host. 19. Since you failed to drop the replication slot, it comes as no surprise that creating a new subscription with the same name (and hence replication slot) fails. logical_replication static parameter and set its value to 1. If upto_lsn and upto_nchanges are NULL, logical decoding will continue until end of WAL. Which can be verified by querying: Quick Setup. To rename a subscription or alter the owner, you must have CREATE permission on the database. Create a logical replication slot and choose a decoding plugin. To find a replication slot, run the following on the primary: SELECT * FROM pg_replication_slots; This allows you to see all the Next. In the case of a walsender, they are encapsulated inside replication protocol WAL messages as described in Section 55. A method of logically replicating data changes from one node ("publisher") to another node ("subscriber"). Returns changes in the slot slot_name, starting from the point from which changes have been consumed last. The former, but it also works for me when restarting the container. You create logical replication slots at 55. Cleanup. May 19, 2020 · pg_recvlogical --version. 6 以降での論理レプリケーションがサポートされています。. drop_subscription('test_sub'). You can also use slot without max_slot_wal_keep_size and monitor WAL folder size to prevent any "storage full" issue – Jun 8, 2018 · Connect to the primary to drop the replication slot. The oldest transaction that this slot needs the database to retain. g. Set the wal_sender_timeout parameter in your database configuration to 0 to disable the timeout. Master Server. Replication slots ensure that the primary does not remove WAL (Write-Ahead Logging) segments until they have been received by all The solution is replication slots, a feature provided by Postgres that ensures the primary server only discards WAL records after they have been received by the standby node. Which I find strange because I'm trying to remove it, not use it. You can use the following commands to list and drop the replication slot: MySQL. pg_create_logical_replication_slot(slot_name name, plugin name) (slot_name name, xlog_position pg_lsn) Creates a new logical (decoding) replication slot named slot_name using the output plugin plugin. PostgreSQL will not remove WAL segments for inactive slots with initialized restart_lsn. It is only needed to prevent postgresql from deleting the old WALs required for logical replication. May 21, 2020 · Missing Piece: Failover of the Logical Replication Slot. We recommend setting alert rules for storage used or storage percentage, and for replication lags, when they exceed certain thresholds so that you can proactively act, increase the storage size, and delete lagging read replicas. Open the custom DB cluster parameter group associated with your RDS for PostgreSQL Multi-AZ DB cluster. A Boolean value of true (or on, yes, 1) tells the backend to go into physical replication walsender mode, wherein a small set of replication commands, shown below, can be issued instead of SQL To drop a replication slot, use the following command: DROP_REPLICATION_SLOT slot_name; Where `slot_name` is the name of the replication slot to be dropped. May 2, 2023 · SELECT pg_drop_replication_slot('name of the slot'); If you need more than 10 replication slots, increase max_replication_slots on the primary and restart it. By default in pg10, all settings are already prepared for replication setup. It is used in the replication configuration like this: archive_cleanup_command = 'pg_archivecleanup archivelocation %r'. logical_replication to 0 in the target DB cluster. Masters can send data, while standbys are always receivers of replicated data. conf (e. In the Parameters search field, locate the rds. ALTER SUBSCRIPTION can change most of the subscription properties that can be specified in CREATE SUBSCRIPTION. Mar 4, 2020 · 5. 27. Next, create a subscription on the target database that subscribes to one or more of the publications from the publisher database. CREATE / ALTER / DROP a database object (TABLE Jul 10, 2023 · The target Aurora PostgreSQL cluster doesn’t need the replication slots. 13GB. Application is working fine if kubernetes deployment strategy is Recreate. However, unless you did something incorrectly (or ran into a bug), you should never be in this situation. The following example shows how to create a replication slot for the `public. SELECT pg_logical_slot_get_changes('slot_name'::text, NULL, null); . 5 ), and the built-in logical replication feature (see Chapter 31 ). select pg_drop_replication_slot('rep_slot'); ERROR: replication slot "rep_slot" is active for PID 162564. Unlike traditional physical replication, which replicates the entire instance along with all the databases, logical replication enables you to replicate a Each replication slot has a name, which can contain lower-case letters, numbers, and the underscore character. Drop the replication slots, and turn off logical replication by setting rds. I got the below warnings, so what are these all about? and Any action is required? postgres=> SELECT pg_drop_replication_slot('abcd_firehose_s3_stream_sl Same as replication protocol command DROP_REPLICATION_SLOT. The first thing is to create a new Postgres database on Amazon RDS (I used version 14. By itself, the replication slot does nothing at all. Once the change is applied, the logical replication slot will be created on the primary node. The standby connects to the primary, which streams WAL records to the standby as they're generated, without waiting for the WAL file to be filled. It is hard to say how you got into trouble, but probably like this: whenever you say CREATE SUBSCRIPTION, the standby connects to the primary and creates a logical replication slot In your Postgres source, change the replication mode to Logical Replication (CDC), and enter the replication slot and publication you just created. Before you can use logical decoding, you must set wal_level to logical and max_replication_slots to at least 1. To execute this command the user must be the owner of the subscription. Nov 20, 2020 · Yes, this is controlled by the publication. If under disk space pressure, remove the replication slot to free up WAL space. I tried to disable it and drop it. logical_replication to 1, the wal_level is set to LOGICAL. With this, The Primary's WAL will keep disc size till 40GB and only if it's necessary. e. database. Apr 17, 2024 · After we found that out using pg_stat_activity and killed blocking process replication slot creation finished and now it's working as expected. pg_recvlogical controls logical decoding replication slots and streams data from such replication slots. A unique, cluster-wide identifier for the replication slot. This tutorial assumes you have already setup streaming replication between a primary and a replica PostgreSQL server. Unfortunately, you have to go through this elaborate dance: alter subscription <sub1> disable; alter subscription <sub1> set (slot_name = none); drop subscription <sub1>; for each subscription, before you can drop the database. this should do the job. active_pid int4. Standby Servers. A replication slot marks a certain WAL position, so that the primary server won't discard any WAL after that position. These settings control the behavior of the built-in streaming replication feature (see Section 27. Replication slot: Physical replication slots are created by cross-Region read replicas or same-Region read replicas only if they are running on PostgreSQL 14. A publication can only be dropped by its owner or a superuser. The slot type: physical or logical. Exception replication slot "XXX" is active for PID XXX as older pod is using the same replication slot Description. You should fix the problem that's causing WAL to be retained. SELECT redo_lsn, slot_name,restart_lsn, round((redo_lsn-restart_lsn) / 1024 / 1024 / 1024, 2) AS GB_behind. Amazon Aurora PostgreSQL 互換エディションのバージョン 2. Postgres Replication Methods The Postgres source currently offers 3 methods of replicating updates to your destination: CDC, xmin and standard (with a user defined cursor). For logical slots, this must be called while connected to the same database the slot was created on. We also discuss their benefits and disadvantages. Sep 14, 2021 · You can use pg_archivecleanup. These messages are either returned by the replication slot SQL interface or are sent by a walsender. Table 52. 6 and Chapter 46. Logical Replication. For streaming replication, servers will be either a primary or a standby server. Engine log + Binlog -> byte encoded -> binlog stream -> binlog apply. Now connect to your Postgres database with pg_recvlogical and create a slot. 4, it is also necessary and useful to check for leftover replication slots. There is a proposal to allow a logical replication slots WAL retention to be limited. Conversely, a value of “t” would indicate that the replication slot is active and is currently being used. Then I check a couple of things : Record count between tables : obviously there is a difference though its only differ by 50 records. Note: The max_slot_wal_keep_size setting can help you avoid storage full issues on the PostgreSQL source. So if you have a logical replication slot associated with database A, replication is stopped, and you generate a lot of WAL with activity in database B, all that WAL has to be retained, even if it does not contain any activity related to A. In Postgres, physical replication can be setup between a primary and one or more standbys without using replication slots. 81. Row_format: Replicates the change or the complete statement. Modifying the DB instance Mar 16, 2018 · First, you create a publication. conf that were specifically set for replication. If it does not work even without Debezium - most likely True if this slot is currently actively being used. As per the docs. Use the function pg_drop_replication_slot() to drop the problematic replication slots, and PostgreSQL will automatically delete old WAL segments after the next checkpoint. You can apply max_slot_wal_keep_size on the source database in PostgreSQL 13 and later. This sets the maximum amount of WAL that can be retained by replication slots. Used replication slots continue to occupy space. Only logical slots have an associated database. Two identical Debian 10 instances. Replication slots are a persistent data structure used to track the progress of replication across subscribers, and to ensure that WAL data needed for replication is not prematurely removed (or recycled). Jan 22, 2020 · maximus_db=# select pg_drop_replication_slot('slot2'); -[ RECORD 1 ]-----+- pg_drop_replication_slot | Monitoring your PostgreSQL replication slots. 4) or via SQL functions (see Section 9. Feb 2, 2016 · you have a replication slot (see the pg_replication_slots view) that's preventing the removal of WAL. One such feature is logical replication using a publish and subscribe framework. Then if you don't want leave it at "archive", set it back to "minimal" again, set max_replication_slots to 0, and restart again. The core issue is that if somebody forgets to drop a replication slot, XLOG can accumulate, just as it does in the case of broken archive commands. Connect with a user that has replication permissions. Create a logical replication slot on the primary node. DROP SUBSCRIPTION cannot be executed inside a transaction block if the subscription is associated with a replication slot. Examples. SELECT slot_name, pg_size_pretty(pg_wal_lsn_diff(pg_current_wal_lsn(),restart_lsn)) AS replicationSlotLag, active FROM pg_replication_slots ; May 17, 2022 · Replication slots mark a certain position in the WAL stream, and all WAL information for the whole cluster is a single stream. Check recovery. answered Sep 14, 2021 at 9:10. Yes, you can do synchronous logical replication, but the usual caveats apply: 1) have short network latency between the nodes 2) expect a sharp decrease in write performance 3) if you have less then two synchronous standby servers, your overall availability will decrease. We would like to show you a description here but the site won’t allow us. First, make sure to download and install the Linux package on each node . 5. postgres. Sorted by: 5. Apr 8, 2018 · 1. For me it is the latter that is causing the replication slot issues. Therefore, it is essential to keep an eye on useless replication slots (physical as well as . ここに示す解決策では、RDS for PostgreSQL の論理レプリケーションを使用して、2 つのソーステーブルが 2 つのターゲット True if this slot is currently actively being used : active_pid int4. For those who might face that issue in the future, try to create a replication slot manually using pg_create_logical_replication_slot(). They aren’t used for physical replication by default, so you’ll only be dealing with them if you enable their use. Table 48-39. 3. Check pg_replication_slots restart_lsn value and compare it with current redo_lsn. , max_wal_senders, wal_level) and pg_hba. True if this slot is currently actively being used. But, it can also cause WAL to be Ensure that your max_replication_slots value is equal to or higher than the number of PostgreSQL connectors that use logical replication plus the number of other replication slots your database uses. Since it is a race, you should arrange to submit the drop command on the same keystroke as the terminate command. RDS for PostgreSQL supports the streaming of write-ahead log (WAL) changes using PostgreSQL's logical replication slots. 0 以降では、PostgreSQL 10. The following example demonstrates controlling logical decoding using the SQL interface. re "pick up" - I docker run one kafka-connect instance, then POST the connector config. plugin name. Whether or not to drop the logical replication slot when the connector finishes orderly. Requirements. The issue I am facing is when the leader/master node goes down and one of the replicas takes over as leader/master node and then over time when the old leader/master rejoins the cluster. 6. ALTER SUBSCRIPTION aaa DISABLE; ALTER SUBSCRIPTION aaa SET (slot_name = NONE); I tried to terminate the backend pid and drop it but at the end nothing worked. Nov 30, 2018 · Physical replication setup is really easy with slots. You can set up logical replication slots on your instance and stream database changes through these slots to a client such as pg_recvlogical. If you need to set that up first, run through this tutorial. We will be setting up streaming replication with replication slots on two Debian 10 nodes. Is Aug 7, 2023 · In this post, we show you how to set up cross-account logical replication using Amazon Aurora PostgreSQL-Compatible Edition. “pgoutput” is the decoding plugin for PostgreSQL logical replication. If you could provide exact steps for reproducing the issue, that'd be great. Feb 25, 2014 · Streaming replication slots are a new facility introduced in PostgreSQL 9. CREATE PUBLICATION foo FOR TABLE herp, derp; Then you subscribe to that publication from another database. On the Primary Server: You don't necessarily have to do anything on the primary server if you're just turning off the replication. 2. 2. Feb 9, 2024 · In PostgreSQL, the “active” column represents whether a replication slot is currently actively being used or not. The base name of the shared object containing the output plugin this logical slot is using, or null for physical slots. 4. on. There are two ways to do this: setup streaming replication without using replication slots; log shipping; Using replication without slots is not so common anymore, but is valid and Jul 9, 2018 · After you set rds. slot_name name. First, identify the maximum number of replication slots. Dec 14, 2023 · Verify that the current streaming replication setup is synchronized and that there is no lag between the primary and standby nodes. This establishes the replication pipeline from source to target. CREATE SUBSCRIPTION mysub CONNECTION <connection stuff> PUBLICATION foo; This creates a replication slot on a master database under the hood and starts listening to updates and commit them to the same Remove used replication slots. stop. A call to this function has the same effect as the replication protocol command Jul 10, 2024 · Abandoned replication slots: Drop the abandoned slots. Make sure you install the necessary dependencies from step 1, add GitLab package repository from step 2. It is a form of "use". Long running transaction on replica, with hot_standby_feedback = on: Identify them and cancel or terminate the backend to unblock the vacuum. oid: The OID of the database this slot is associated Note: The following commands check whether there are any inactive replication slots, determine the respective sizes of the slots, and then drop the slots, if required. Apr 12, 2020 · CREATE SUBSCRIPTION my_subscription CONNECTION 'host=localhost port=5432 password=my_password user=my_user dbname=db' PUBLICATION my_publication WITH (slot_name=test_slot_v1, create_slot=false); alter subscription my_subscription refresh publication ; First replication works. " slot. Slots can be created and dropped either via the streaming replication protocol (see Section 55. pg_create_physical_replication_slot() is a system function for creating a physical replication slot. 4, and generally obey the same message flow as physical replication. 5 on the free tier). Subset of SQL, used for defining and managing the structure of a database. SELECT * FROM pg_stat_replication; answered Nov 20, 2022 at 11:56. com Learn how to use replication slots with PostgreSQL's streaming physical replication. Values must conform to Postgres replication slot naming rules which state: “Each replication slot has a name, which can contain lower-case letters, numbers, and the underscore character. DDL--Data Definition Language. The OID of the database this slot is associated with, or null. 1 and higher versions; Logical replication slots are created for a replica or subscriber; Bloat or improper removal of dead rows; Presence of orphaned files; 3. Jun 11, 2018 · Once you discover you have a replica that fell back, you have to investigate why it did so, and fix it - or remove the host from Patroni altogether. The process ID of the session using this slot if the slot is currently actively being used. The default authentication assumes that you are either logging in as or sudo’ing to the postgres account on the host. Whether or not to delete the logical replication slot when the connector stops in a graceful, expected way. Find out how much behind is the subscriber : 5. slot. catalog_xmin xid Aug 23, 2022 · Obviously, the replication slot is inactive. Then get a session on the database and create a replication slot like this: 1. The name of the Postgres logical decoding slot created for streaming changes from a plugin and database instance. The reason is that someone, for example a replication standby, will still To set up logical replication for an RDS for PostgreSQL Multi-AZ DB cluster. Jun 11, 2018 · PostgreSQL will not automatically remove the slot, you need to do it manually using pg_drop_replication_slot. Streaming replication allows a standby server to stay more up-to-date than is possible with file-based log shipping. 234k 19 255 323. 1. Dec 21, 2021 · A replication slot is a feature in PostgreSQL that ensures that the master server will retain the WAL logs that are needed by the replicas So you need to monitor the slots and manually drop This is what your output_plugin should do - required second argument to pg_create_logical_replication_slot function. slot_type: text : The slot type - physical or logical: datoid: oid: pg_database. Root access to both instances. Next. From the shell, you could lock out the replication client via pg_hba. Create publication for tables on the primary node. You can use the following query and check for client_addr, client_port, and client_hostname. Ronak Jain. The base name of the shared object containing the output plugin this logical slot is 2 days ago · On the primary, query the pg_replication_slots table to see the replication slot created by the subscription. We use the term logical in contrast to physical replication, which uses exact block addresses and byte-by-byte replication. Then when i change the value of one varchar entry (not a FK), the The pg_replication_slots view provides a listing of all replication slots that currently exist on the database cluster, along with their current state. AWS provides two managed PostgreSQL options: Amazon RDS for PostgreSQL and Amazon Aurora PostgreSQL. Jan 13, 2022 · The “ slots:” section defines permanent replication slots. 3. orders` table in the `mydb` database: CREATE_REPLICATION_SLOT my_slot. For more on replication slots, see Section 26. See PostgreSQL CREATE PUBLICATION / SUBSCRIPTION. Jul 13, 2020 · If you can't do that, then you have to terminate the wal sender and then drop the slot before it has a chance to start up again. Cross-engine Events are append to the binlog (unless skipped sql_log_bin) Slaves filter using do%. Logical Decoding Examples #. But Throwing exception on using RollingUpdate Deployment strategy. This parameter change can increase WAL generation, so Jun 27, 2024 · The pg_replication_slots view provides a listing of all replication slots that currently exist on the database cluster, along with their current state. 6 and Chapter 47. ” Type: string; Importance: medium Nov 19, 2022 · 1. pg_create_physical_replication_slot() was added in PostgreSQL 9. com -U rachel@pgserver -d postgres --slot logical_slot --create-slot -P wal2json. Then, remove the unused replication slots. They are a persistent record of the state of a replica that is kept on the master server even when the replica is offline and disconnected. 4, while logical replication slots were added beginning with version 10. pg_create_logical_replication_slot ( slot_name name, plugin name [, temporary boolean, twophase boolean] ) → record ( slot_name name, lsn pg_lsn) Creates a new logical (decoding Jun 20, 2018 · Values must conform to Postgres replication slot naming rules which state: "Each replication slot has a name, which can contain lower-case letters, numbers, and the underscore character. pg_replication_slots Columns. When the connector restarts, having the same replication slot enables the connector to start processing where it left off. When installing the GitLab package, do not supply EXTERNAL_URL value. You must own the subscription to use ALTER SUBSCRIPTION. I think that that is just what you need, but it is not clear when/if it will become available. You can see what slots you have by querying pg_replication_slots, and if necessary drop one with pg_drop_replication_slot, both run on 49. Same as replication protocol command DROP_REPLICATION_SLOT. Then start the slot. drop. As a superuser, you can kill the WAL sender process with the pg_terminate_backend function and drop the replication slot before Installing the Linux package. Then, you should connect to the target database (in the example below, postgres) as a superuser. Existing replication slots and their state can be seen in the pg_replication_slots view. In this post, you have one replication slot called replication_slot. Logical decoding capability has existed in PostgreSQL for the last several versions, and a lot more functionalities are added over time. DROP PUBLICATION removes an existing publication from the database. Two-phase Commit Support for Logical Decoding. It creates a replication-mode connection, so it is subject to the same constraints as pg_receivewal, plus those for logical replication (see Chapter 49 ). hm vk pi co dg ck yi jd ki qn