SEARCH KEYWORD -- Correlated query

  4 deployment modes of Redis

As a high-performance in-memory database, Redis is widely used in current mainstream distributed architecture systems. To improve system fault tolerance, using multiple instances of Redis is also inevitable, but the complexity is much higher than that of a single instance. This article mainly introduces the four deployment modes of Redis and their advantages and disadvantages. Standalone Standalone mode is to install a Redis, start it, and business connects to it and that's all. The specific ...

   REDIS,STANDALONE,MASTER-SLAVE,SENTINEL,CLUSTER     2023-03-03 21:35:09

  Why (offset, limit) is slow in database select?

Starting from a problem Five years ago when I was working at Tencent, I found that MySQL request speed was very slow in the pagination scenario. With only 100,000 data, a select query on a single machine took about 2-3 seconds. I asked my mentor why, and he asked in return, "In an indexing scenario, what is the time complexity to get the nth largest number in MySQL?" The pursuit of the answer Confirming the scenario Assuming there is an index on the "status" column, a query like "select * from t...

   SLOW,LIMIT,OFFSET,MYSQL     2023-03-12 05:21:02

  Your Ultimate Guide to Restoring Database Backups in SQL Server 2012

Summary: Let’s learn how to restore a SQL Server database backup for SQL Server 2012. There are various methods of taking database backups, which include using T-SQL code, SQL Server Management Studio, or third-party applications. These backups taken are purposely saved to be restored when the database becomes corrupt or crashes, migrating the database, making a copy of the database, and other business requirements. In this crash course, we will be focusing on how to restore SQL Server da...

   BACKUP,MSSQL     2024-09-24 09:38:09

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