postgresql 12 replication

1. What is PostgreSQL replication?
2. How does Postgres replication work?
3. How many types of replication are there in PostgreSQL?
4. How does logical replication work in PostgreSQL?
5. How does MongoDB replication work?
6. What is replication slot?
7. What is streaming in PostgreSQL?
8. Can Postgres scale horizontally?
9. Does PostgreSQL support sharding?
10. How many types of replication are there?
11. What are the types of replication?
12. What is asynchronous replication in PostgreSQL?

What is PostgreSQL replication?

What Is PostgreSQL Replication? The process of copying data from a PostgreSQL database server to another server is called PostgreSQL Replication. The source database server is usually called the Master server, whereas the database server receiving the copied data is called the Replica server.

How does Postgres replication work?

Understanding replication in PostgreSQL

Streaming replication in PostgreSQL works on log shipping. Every transaction in postgres is written to a transaction log called WAL (write-ahead log) to achieve durability. A slave uses these WAL segments to continuously replicate changes from its master.

How many types of replication are there in PostgreSQL?

PostgreSQL comes with three different replication methods. As with so many things, each replication method has its pros and cons.

How does logical replication work in PostgreSQL?

In logical replication, also known as transactional replication, the subscriber initially receives a copy of the replicated database object from the publisher and pulls any subsequent changes on the same object as they occur in real-time.

How does MongoDB replication work?

Replication in MongoDB

Of the data bearing nodes, one and only one member is deemed the primary node, while the other nodes are deemed secondary nodes. ... The secondaries replicate the primary's oplog and apply the operations to their data sets such that the secondaries' data sets reflect the primary's data set.

What is replication slot?

What are replication slots? Streaming replication slots are a new facility introduced in PostgreSQL 9.4. 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.

What is streaming in PostgreSQL?

From PostgreSQL wiki. Streaming Replication (SR) provides the capability to continuously ship and apply the WAL XLOG records to some number of standby servers in order to keep them current. This feature was added to PostgreSQL 9.0.

Can Postgres scale horizontally?

For Horizontal Scaling, we can add more database nodes as slave nodes. It can help us to improve the read performance balancing the traffic between the nodes. In this case, we'll need to add a load balancer to distribute traffic to the correct node depending on the policy and the node state.

Does PostgreSQL support sharding?

In fact, PostgreSQL has implemented sharding on top of partitioning by allowing any given partition of a partitioned table to be hosted by a remote server. The basis for this is in PostgreSQL's Foreign Data Wrapper (FDW) support, which has been a part of the core of PostgreSQL for a long time.

How many types of replication are there?

There are four MS SQL Server replication types: snapshot replication, transactional replication, peer-to-peer replication and merge replication.

What are the types of replication?

Types of data replication

• Full table replication.
• Transactional replication.
• Snapshot replication.
• Merge replication.
• Key-based incremental replication.

What is asynchronous replication in PostgreSQL?

PostgreSQL streaming replication is asynchronous by default. If the primary server crashes then some transactions that were committed may not have been replicated to the standby server, causing data loss. ... The only possibility that data can be lost is if both the primary and the standby suffer crashes at the same time.