What Is Polardb for Postgresql?

PolarDB for PostgreSQL is a cloud-native database solution provided by Alibaba Cloud that is designed to offer high performance, scalability, and full compatibility with PostgreSQL. In this article, We will learn about What Is Polardb for PostgreSQL by understanding their Features, Examples and so on.

What is PolarDB for PostgreSQL?

• PolarDB for PostgreSQL is a cloud-native database service offered by Alibaba Cloud.
  
• It's designed to provide high performance, scalability and compatibility with PostgreSQL and making it suitable for large-scale applications.
  
• PolarDB is fully compatible with standard PostgreSQL. Applications and tools that work with PostgreSQL can be used with no modification.

Key Features PolarDB for PostgreSQL

• High Performance: Optimized to process high-speed queries and transactions six times faster compared to standard PostgreSQL.
  
• Auto-Scaling: Scale up to 100 TB of storage without requiring downtime and is well-suited applications that have growth.
  
• Cloud Native Architecture: Distributed storage and shared-everything architecture for greater availability as well as durability.
  
• Compatibility with PostgreSQL: Applications developed on standard PostgreSQL can easily be migrated to PolarDB with minimal code modification.
  
• Multi-Zone Availability: It provides multi-zone deployment for the same reason as a way toward better disaster recoverability and fault tolerance
  
• Read-Write Splitting: PolarDB supports multiple read replicas and allows the option of splitting read/write operations to improve performance.

PolarDB for PostgreSQL Architecture

PolarDB for PostgreSQL's architecture is designed for the challenges faced by the shortcomings of the traditional database and thats how it uses cloud infrastructure. The core parts of this architecture are as follows:

• Shared Distributed Storage: PolarDB separates the storage layer entirely from the compute layer, so it can scale them separately. In simple words, this is a high-availability-based storage system with high-speed failover facilities in case of node failure.
  
• Read-Write Splitting: PolarDB supports multiplicity of read replicas that share the same distributed storage. It thus can smoothly support read-write splitting. All the writes requests are processed by the master node, while all the requests seeking to read are handled by replicas.
  
• Multi-Node Architecture: PolarDB provides a way to deploy multiple compute nodes sharing the same storage but able to independently process a query. Thus, it leads to horizontal scaling without data replication delays.

Differences Between PolarDB and Traditional PostgreSQL

Advantages of PolarDB for PostgreSQL

• Better Performance: PolarDB provides immense performance advantages and is specifically designed for workloads with many reads as it pursues read-write splitting and shared storage.
  
• With elastic scalability, you can scale up to 100TB storage without interruption-making it a suitable solution for applications with unpredictable growth.
  
• Reduced Maintenance: PolarDB automatically creates backups, patches, and updates to reduce the overhead associated with database administration.
  
• High Availability and Fault Tolerance The multi-zone architecture of PolarDB ensures data availability even in cases of zone failures.
  
• Cost Efficiency: PolarDB is a cloud-native offering and uses a pay-as-you-go pricing model that is much costlier than running traditional hardware and storage.

Common Use Cases

This is why PolarDB ranks first in processing many high-scale transactions and operations by dividing read-write operations, making it suitable for highly trafficked online shopping e-commerce sites.

• Data-Intensive Web Applications. PolarDB ensures read-heavy workloads are distributed across multiple replicas for websites or services processing high volumes of queries that require high availability.
  
• Enterprise resource planning ERP systems: PolarDB is scalable and provides high availability so that the enterprise can develop its business with the growth of the same ERP.
  
• High-Performing Financial Applications: PolarDB provides inherent failover capabilities and low-latency performance to deliver resilient mission-critical financial applications.

Examples

Example 1: Creating PolarDB for PostgreSQL

To create a PolarDB for PostgreSQL cluster in Alibaba Cloud, follow the process using the web console as described below:

Step 1: Access Alibaba Cloud Console:

• Go to the PolarDB section.
• Click on Create Cluster.

Step 2: Select Database Engine as PostgreSQL:

• Next, select PostgreSQL as the database engine.
• Select your PostgreSQL version, say PostgreSQL 11 or 12.

Step 3: Configure Cluster Settings:

• Allow setting up the primary zone for the cluster for high availability purposes.
• Also, define the backup zones.
• Select your vCPU and RAM with regard to your workload needs.

Step 4: Auto-Scaling Configuration

• Enable automated storage scaling which ensures that the storage goes up only when needed and with no downtime. Cluster Creation
• Click create and PolarDB will provision your PostgreSQL cluster in a few minutes.

Example 2: Read-Write Splitting with PolarDB for PostgreSQL

PolarDB allows us to perform read-write splitting by using a primary node for writes and read-only nodes for read operations.

• Identify the Read-Only Endpoint: Once your cluster is running, PolarDB automatically provides a read-only endpoint. You can find this in the PolarDB Console under Cluster Endpoints.
  
• Configure Read-Write Splitting: Modify your application's database connection string to route write queries to the primary node and read queries to the read-only replicas.

# Write endpoint (Primary node)
primary_db_connection = "postgresql://username:password@primary_endpoint/dbname"

# Read endpoint (Read replicas)
read_replica_db_connection = "postgresql://username:password@readonly_endpoint/dbname"

Execute Queries: For read-heavy applications, route all SELECT queries to the read-replica endpoints, and INSERT/UPDATE/DELETE queries to the primary node.

Example SQL for the Primary (Write Node):

INSERT INTO users (username, email) VALUES ('alice', '[email protected]');

Example SQL for the Read-Only Nodes:

SELECT * FROM users WHERE username = 'alice';

Conclusion

PolarDB for PostgreSQL is a powerful, cloud-native database service that excels in scalability, performance, and availability. With features such as automatic scaling, read-write splitting, and high availability through multi-zone deployment, PolarDB addresses the needs of businesses running data-intensive applications. Its compatibility with PostgreSQL ensures smooth migrations, while its pay-as-you-go pricing model offers cost efficiency.