How to reset or empty the data of scrapy-redis 's dupefilter?
after you have climbed with scrapy-redis spiders, you will not be able to climb again. If you change the name of the spider, you can crawl again, and if you change back to the original name, you will start the deduplication mechanism again. Although you...
Tp5 uses redis, to add extension guidance
how do you tp5 encapsulate the extension function of redis? Because there are only simple functions of set and get by default, guide me. ...
Annotation invalidation of dao interface using mybatis @ CacheNamespace cache
use mybatis to configure custom secondary cache. Using xml annotation can use < cache type= "com.test.dao.MybatisRedisCache " > to successfully use custom cache, but using @ CacheNamespace (implementation = MybatisRedisCache.class) on the dao i...
Redis backup recovery
redis server, with only one node. I am inserting a piece of data,
. set 1 1
. get 1
. del 1
. get 1 nil
7. dumps.rdb var lib redis
9. get 1
data backup is not restored. I would like to ask what is th...
Redis acts as a message queue to control the consumption interval of the queue.
has encountered a difficult problem recently.
I use redis for message queuing. Each queue contains a task id,
the simple process is as follows:
1. Read id, consumption from list
2. Read the details of this task from the database according to id,...
Redis server went away
< H1 > 1. Problem description < H1 >
No error is reported when the command line runs, and: redis server went away error occurs in the form of browser access server script
< H1 > Test Code: < H1 >
< H1 > problem speculation < H1 >
How does the user code perceive the current master and slave of the cluster after the master-slave switch of the redis sentinel cluster?
how does the user code perceive which instance of the current master is after the master-slave switch of the redis sentinel cluster? Thus write to the current main library. Thank you for your guidance ~ ...
What is the difference between Redis queues and message queues?
recently I saw an article https: codeshelper.com a 11. with two sentences like this:
suddenly don t understand the similarities and differences between redis queues and redis message queues? What scenari...
How to extract session from redis in laravel5.5
because of the need for sso single sign-on, different servers and the same domain name, the user center plans to develop with laravel, in which session is shared in redis. How to obtain session in laravel projects for other projects. Ask for guidance. ...
Redis enables rdb persistence Why can't I update rdb files?
I am a win7 system and successfully installed redis,. Now I have configured in the configuration file.
save 900 1
save 300 10
save 60 10000
rdb persistence is supposed to be enabled, but after set and get operations, the file has not been up...
Redis connection pool
ask a question: 1-100 servers, each service maintains a globalredis pool; (is connected to a redis)
will there be too many global redis connections? there is no maintenance pool, so turn it off after using it .
the local redis is maintained by a ...
Won't redis cleanup expired keys block?
assume that concurrency is very high, with 1 million keys being put into redis, at the same time per second and with the same expiration time
so redis cleans up 1 million keys at the same time, without blocking?
How to correctly use redis queue to deal with php second kill concurrency problem?
Baidu found this way of thinking: needs a queue, a queue of panic buying results and a queue of inventory. In the case of high concurrency, first put the user into the queue, use a thread loop to remove a user from the queue, and judge whether the user...
Apart from caching mysql data to improve concurrent read performance, what other application scenarios does Redis have?
as we all know, Redis can be well used in data caching scenarios, which can greatly improve the read and write efficiency compared to MySQL. however, I have found that many of the application scenarios advertised by Redis enthusiasts actually do not ex...
How to prevent a large number of queries from penetrating the cache when the Redis cache fails
suppose we have a sql query that will take 2 seconds. We cache the results of this sql query to redis and set a 60-second timeout. so when 60 seconds arrive, that is, two seconds from 60 to 62 seconds, hundreds of requests may miss the cache and query ...
How to realize the operation of buying tickets in cinemas to prevent the phenomenon of buying more than one ticket?
recently, a project is a theater ticket management system, but the ticket module does not know how to implement it. At first, it uses the transaction and locking mechanism of MySQL database, but there are still some problems. Finally, I think about wheth...
After the order exceeds a certain time, the user does not confirm the receipt of the goods, which requires the system to automatically complete the confirmation operation, that is, to change the status of the order. Do you have any good ideas?
after the order exceeds a certain time, the user does not confirm the receipt, so the system needs to automatically complete the confirmation operation, that is, to change the status of the order. Do you have any good ideas?
I have seen before that so...
How does django solve the problem of creating users in bulk?
A registration function. The function of accessing the registered url, url is to read the user names and passwords of 500 users from the excel file, read out a piece of data, run the create_user function at a time to create a user, but this will cause t...
Docker uses compose and swarm as redis master-slave cluster
recently I am using docker to learn redis, when I see that redis can be the master and slave, I use docker to deploy the service. In some businesses that need to be cached, there are some problems that I haven t thought clearly in my mind .
About how to use laravel queues for asynchronous no-delay execution
you need to use laravel queues (redis drivers) to implement code execution asynchronously without delay, such as
$stock = 5; $job = new DecStock (); $this- > dispatch ($job);
the purpose is to return the variable $stock as soon as...