• Optimize PostgreSQL autovacuum


    Author: laurenz albe is a senior consultant and support engineer of cybertec. He has been working on and contributing to PostgreSQL since 2006. Translator: Lei Yanliang, working in Henkel basic software Co., Ltd., a PostgreSQL database technology enthusiast, 10g &11g OCM, Ogg Certified Expert. In many PostgreSQL databases, you don’t need to consider or worry […]

  • Producer confirm of PHP actual combat rabbitmq


    brief introduction In order to improve the high availability of the system, the producer is sendingmessageNeed to passMQreplyACKTo ensuremessageSuccessfully stored. Note: WeChat official account: Architect’s Road RabbitMQPublisher confirms is introduced on the official website. UnfortunatelyexampleNo codephpVersion, andphp-amqplibIt is also a group of volunteers who have limited energy in maintenance and do not use example completely […]

  • PostgreSQL: you may need to add max_ LOCKS_ PER_ TRANSACTION


    Author:Hans J ü rgensch ö nig, he has used PostgreSQL since the 1990s. He is the CEO and technical leader of cybertec. Cybertec is one of the market leaders in this field and has provided services to countless customers around the world since 2000. The second edition of PostgreSQL 9 and PostgreSQL 6 has been […]

  • Spring framework learning


    Advantages of spring Spring is an open source and free framework Spring is a lightweight, non intrusive framework Inversion of control (IOC), aspect oriented programming (AOP) Support transaction processing and framework integration Spring is a lightweight inversion of control (IOC), aspect oriented programming (AOP) framework IOC essence Inversion of control (IOC) is a design idea. […]

  • Android serialization 36 – query data, use of native SQL and use of transactions


    1、 Query data Android’s query database operation is very complex. Sqlitedatabase uses the query method to find data, which contains many parameters. Let’s take a look Query() method parameters Corresponding SQL part describe table from table_name Table name colums select colum1,colum2 Column name to query selection where column = value constraint condition selectionArgs – Provide […]

  • What is the use of log buffer?


    The log buffer is the memory area that holds data to be written to the log files on disk. Log buffer size is defined by the innodb_log_buffer_size variable. The default size is 16MB. The contents of the log buffer are periodically flushed to disk. A large log buffer enables large transactions to run without the […]

  • Meaning and difference between MySQL row lock and table lock


    It is impossible that every day is a good day. When there are bad days, the good days will shine. 1、 Foreword The meaning difference between row lock and table lock should appear frequently in the interview. We should have a systematic understanding of the lock in MySQL. We need to consult the data in […]

  • How does oracle19c use benchmark SQL data exchange?


    oraclemyasm benchmarksql-5.0]$ export JAVA_TOOL_OPTIONS=-Dfile.encoding=UTF8[oraclemyasm benchmarksql-5.0]$ antPicked up JAVA_TOOL_OPTIONS: -Dfile.encoding=UTF8Buildfile: build.xmlinit:compile: [javac] Compiling 11 source files to /soft/tpcc/benchmarksql-5.0/build dist: [mkdir] Created dir: /soft/tpcc/benchmarksql-5.0/dist [jar] Building jar: /soft/tpcc/benchmarksql-5.0/dist/BenchmarkSQL-5.0.jar BUILD SUCCESSFULTotal time: 14 secondsdb=oracledriver=oracle.jdbc.driver.OracleDriveruser=mytestpassword=oraclewarehouses=10loadWorkers=4terminals=10//To run specified transactions per terminal- runMins must equal zerorunTxnsPerTerminal=0//To run for specified minutes- runTxnsPerTerminal must equal zerorunMins=10//Number of total transactions per minutelimitTxnsPerMin=300//Set to true […]

  • Leverage swoole_ Process and EventLoop for PHP asynchronous programming


    The idea is simple: Start a child process to process asynchronous transactions. After processing, tell the parent process through the pipeline and write the returned data to the pipeline The code is as follows: AsynHttpClient.php <?php class AsynHttpClient { public $url; public $callback; private $process; public function __construct($url, $callback) { $this->url = $url; $this->callback = […]

  • How to implement distributed transactions under microservice architecture?


    abstract: how to overcome the problem of distributed transaction under microservice architecture? What is micro service? What are the advantages and difficulties of microservices? What is a microservice architecture? In short, the microservice architecture system is a distributed system, which is divided into independent service units according to business, which not only solves the shortcomings […]

  • Interviewer: how to deal with tens of millions and hundreds of millions of traffic?


    The last and final part of this series of “I want to enter the big factory”. It may be a bit of a title party, but the meaning and purpose I want to express are the same. This is a very common interview question, but most people don’t know how to answer it. In fact, […]

  • Type of MySQL lock


    Lock based attribute classification: shared lock and exclusive lock.Lock based granularity classification: row level lock (InnoDB), table level lock (InnoDB, MyISAM), page level lock (BDB engine), record lock and inter lockGap lock, temporary key lock.Lock based state classification: intentional shared lock and intentional exclusive lock. Share lock Shared lock, also known as read lock, is […]