Today's Question:  What does your personal desk look like?        GIVE A SHOUT

SEARCH KEYWORD -- Complexity

  Signs that you're a bad programmer

1. Inability to reason about codeReasoning about code means being able to follow the execution path ("running the program in your head") while knowing what the goal of the code is.SymptomsThe presence of "voodoo code", or code that has no effect on the goal of the program but is diligently maintained anyway (such as initializing variables that are never used, calling functions that are irrelevant to the goal, producing output that is not used, etc.)Executing idempotent functions multiple times (...

   Sign,Programmer,Characteristics,Knowledge,Skill     2011-10-20 08:56:16

  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

RECENT