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I Redis (in memory nosql database) NoSQL and RDBMS 1.1: the characteristics of RDBMS (relational database mysql): it reflects the relationship between data, supports transactions, ensures the integrity and stability of business, and has good performance with a small amount of data. However, high concurrency will lead to database crash. 1.2 NoS ...

1. What is the bloom filter2. Characteristics of Bloom filter3. Usage scenario of Bloom filter4. Principle of Bloom filter5. Advantages and disadvantages of Bloom filter6. Application of Bloom filter7. Summary 1. What is the bloom filterThe bloom filter of redis is actually a bit like the hyperlog we learned before In depth understanding of red ...

Technical research background As the current R & D team is in the start-up stage of the company, there is no mature operation and maintenance system, and the ability to build and maintain the mature MQ commonly seen in the market is insufficient. However, we hope to have a lightweight message system for the members of the R & D team. T ...

Concept: Idempotency, in popular terms, is an interface that initiates the same request multiple times. It must be ensured that the operation can only be executed once For example: Order interface, cannot create order more than oncePayment interface. You can only deduct money once for repeated payment of the same orderThe callback interface ...

Preface As a cached database, Redis currently has a large usage in the market. Most people use its string format storage in their work. For the rest of the data structure, it is rarely used. The basic data structure of Redis includes: string, hash, list, set, sorted set. These five data structures are often used in different scenarios in ...

Nosql overview Why use Nosql Stand alone MySQL Era In the 1990s, the number of visits to a website was generally not too large, and a single database was sufficient. However, with the increase of users, the following problems occurred: The amount of data is too large for one machineThe index of data (B+ tree) can't fit into a machine's m ...

Here, I use the jar package spring boot starter data redis of redisTemplate combined with spring boot framework, which is introduced in the way of POM. The introduction code is as follows: <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <versi ...

1, ForewordOfficial document address: https://lettuce.io/core/5.3.7...  recently, due to work requirements, we need to understand some implementation principles of lettuce. As can be seen from the directory of the official documents, lettuce implements a wealth of business functions, supports three execution modes: synchronous blocking, Fu ...

1, Global command 1. Query key Keys * query all keys and traverse all key values, complexity O(n) 2. Total number of keys dbsize queries the total number of keys and directly obtains the total number of keys variable built in redis. The complexity is O(1) 3. Check whether the key exists exists key returns 1 if it exists and 0 if it does n ...

1, Node At the beginning, each Redis instance is A cluster itself. The work of connecting each node is completed through the CLUSTER MEET command. After A and B shake hands, A will spread B's information to other nodes in A's cluster through the Gossip protocol, so that other nodes can also shake hands with B; // Cluster nodes struct cluster ...