• Oracle — sqlpatch of fixed execution plan


    Today, let’s do a test using sqlpatch fixed execution plan 1. Use table for test create table tab2(c1 number, c2 number, c3 varchar2(10)); declare a number; begin a := 1; for i in 1 .. 50 loop for j in 1 .. 100 loop insert into tab2 values(a,j,’a’); commit; a := a+1; end loop; end […]

  • Oracle — sqlprofile of fixed execution plan


    Today, I’d like to talk about another method of fixed execution plan: sqlprofile. 1. Obtain the implementation plan without hint. SQL> conn test/test It’s going to go on. SQL> explain plan for select * from tab2 where c2=2; The analysis of the meaning of the word されました. SQL> select * from table (dbms_xplan.display(format=>’advanced’)); PLAN_TABLE_OUTPUT ———————————————————————————————————————— […]

  • Open source! Path planning algorithms commonly used in Robotics (including animation)


    [introduction]: an open source library for path planning algorithms commonly used in robotics, as well as an intuitive demonstration of the running process by moving pictures. The library has not been open for a long time and has 1200 + stars in GitHub. brief introduction In the field of robot research, given a specific task, […]

  • SQL Server view current session state_ [reprinted by whoisactive]


    1、 Common and simple ways Generally, DBAs use sp_ Who and SP_ Who 2 system stored procedure or activity monitor to view the current session, user and process in the SQL instance. We can also identify blocking sessions and active sessions from these processes. 1.1. Sp_ Who is as follows: 1.2 Sp_ Who 2 is […]

  • Cloud box “remote backup” is coming! Automatic remote full backup and incremental backup


    The primary task of cloud box is to back up the document data on the office computers, mobile phones, tablets and other devices of enterprise employees. For enterprises, documents are very valuable data assets, and multi-level backup and restore strategies must be deployed to prevent accidents.The new “remote backup” function of cloud box sends the […]

  • Oracle — Outline of fixed execution plan


    Today we introduce an old method of fixing execution plan: outline.Although this method is relatively old, because there is no version limit, Se can also be used, so it can be used in certain scenarios. The following are the detailed steps and test results: 1. Test is made of table. create table tab1(c1 number, c2 […]

  • Oracle — SPM of fixed execution plan


    Today, we finally talked about SPM, a SQL execution plan fixed method officially recommended by Oracle. Why does the most commonly used method come to the end? Because most of the public information about how to use SPM and the interface provided by Oracle are also the most abundant, if you use a few hundred […]

  • Hive architecture and interpretation of hive SQL execution process


    1、The background of hive The inconvenience of MapReduce programming The file on HDFS lacks schema (table name, name, ID, etc., which is a collection of database objects) 2、What is hive What are the scenarios for hive? Do some data cleaning (ETL), report and data analysis based on Hadoop The structured data file can be mapped […]

  • Using laravel to make MySQL database backup plan


    The translation first appeared inUsing laravel to make MySQL database backup planPlease indicate the source of the reprint. You can export the whole database by running a single command in the terminal. This scheme is not only simple and direct, but also effective. But there are more automated solutions. Let’s see what it is! background […]

  • SQL server automatically back up and regularly clean up backup files


    In our existing system, the importance of database is self-evident. In order to avoid data loss caused by data downtime or misoperation, it is necessary to backup the database regularly. The following will introduce the database backup method of SQL server, hoping to help you solve the problem of daily backup. Step 1: login Database […]

  • Using PG_ SHOW_ Plans monitoring PostgreSQL execution plan


    Author: cybertecLei Yanliang, a PostgreSQL database technology enthusiast, 10g & 11g OCM, Ogg Certified Expert, works in Hangao basic software Co., Ltd Monitoring PostgreSQL execution planpg_ show_ Plans is a free PostgreSQL tool that allows you to monitor execution plans in real time. So far, the query plan cannot be monitored while the SQL statement […]

  • First knowledge of distributed graph database, nebula graph 2.0 query engine


    Absrtact: This paper mainly introduces the overall structure of the query layer, and introduces the flow through the four main modules of the query layer through an ngql statement. 1、 Overview Compared with version 1.0, the distributed graph database version 2.0 has a big change. The most obvious change is that in version 1.0, the […]