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Install K8S on VM and spring boot integration.

Installation Environment Vmware Workstation pro  It is recommended to use the  snapshot  to store the state of each installation stage to avoid installation failures and causing the installation to start from scratch. Ubuntu 22.04 windows 11 Hardware settings  create 3 VM: 4 cores and 4G memory and 100G capacity Before installing K8s (All use the root user) set host: 192.168.47.135 master 192.168.47.131 node1 192.168.47.132 node2 set root ssh connection: sudo su - echo "PermitRootLogin yes" >> /etc/ssh/sshd_config systemctl restart sshd sudo passwd ssh-keygen for i in {master,node1,node2}; do  ssh-copy-id root@$i; done set Ipvs and conf  create conf file: for i in {master,node1,node2}; do ssh root@$i 'cat << EOF > /etc/modules-load.d/containerd.conf overlay br_netfilter EOF'; done execute conf: for i in {master,node1,node2}; do ssh root@$i 'modprobe overlay;modprobe br_netfilter;'; done create 99-kubernetes-cri.conf file: for i in {maste...
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ShardingSphere

 ShardingSphere

The distributed SQL transaction & query engine for data sharding, scaling, encryption, and more - on any database.

ShardingJDBC

ShardingSphere-JDBC is a lightweight Java framework that provides additional services at Java’s JDBC layer.

ShardingProxy

ShardingSphere-Proxy is a transparent database proxy, providing a database server that encapsulates database binary protocol to support heterogeneous languages.



Core Concept

1. Virtual Database

Provides a virtual database with sharding capabilities, allowing applications to be easily used as a single database

2. Real Database

The database that stores real data in the shardingShereDatasource instance for use by ShardingSphere

3. Logic Table

Tables used by the application

4. Real Table

In the table that stores real data, the data structure is the same as the logical table. The application maintains the mapping between the logical table and the real table. All real tables map to ShardingSphere's virtual tables.

5. Distributed primary key algorithm

To create logical table primary keys, ShardingSphere integrates a variety of distributed primary key algorithms and supports the application of custom primary key algorithms.

6. Sharding Strategy

Including the shard key and shard algorithm, the shard key is the vital part of the horizontal shard, without the shard key the ShardingSphere will scan all the tables and lower the performance.
The shard algorithm will find the mapping of the real table by the shard key

Shard Algorithm

1. Inline
2. Standard
3. Complex_inline
4. CLASS_BASED, Custom shard algorithm
5. Hint_inline

The core module of database adaptors

1. SQL Parser

It is divided into the lexical parser and syntactic parser. SQL is first split into indivisible words through a lexical parser.

The syntactic parser is then used to analyze SQL and ultimately extract the parsing context, which can include tables, options, ordering items, grouping items, aggregation functions, pagination information, query conditions, and placeholders that may be modified.

2. SQL Route

The sharding strategy configured by the user is matched according to the parsing context and the routing path is generated. Currently, sharding routers and broadcast routers are supported.

3. SQL Rewriter

Rewrite SQL into statements that can be executed correctly in a real database. SQL rewriting is divided into rewriting for correctness and rewriting for optimization.

4. SQL Executor

It executes asynchronously through a multithreaded executor, focusing more on database connection and memory usage. 

5. Result Merger

It merges multiple execution result sets to achieve output through the unified JDBC interface. The resulting merger includes the stream merger, memory merger, and appended merger using decorator mode.

Distributed transactions

ShardingSphere provides a variety of distributed transactions such as XA and SEATA.


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GC Basic Algorithm

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OS basic

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Thread and concurrency

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