Because the company is busy recently, I forgot to update it. Then I talked about it in the last article, The last article said This article describes some preparations for installing oushudb. This article mainly talks about the installation of corresponding components before installing oushudb.
1, Zookeper installation 1. Create a zkhostfile c ...
Posted by Chips on Sat, 30 Apr 2022 00:19:07 +0300
This article is shared from Huawei cloud community "developing big data SQL Engine from scratch", author: JavaEdge.
Learn the core principles of big data technology, master some efficient ways of thinking and thinking, and build your own technical knowledge system.
We can deduce and even realize various principles without understand ...
Posted by simonyuriko on Fri, 29 Apr 2022 17:24:06 +0300
Svg transforms shapes created in SVG images. For example, move, scale, and rotate shapes. This is a convenient way to display vertical or diagonal text.
1, Simple example of conversion
<rect x="50" y="50" height="110" width="110"
Posted by veroaero on Fri, 29 Apr 2022 04:10:26 +0300
Xiaobai installed some custom services on cdh for the first time, and stepped on a lot of holes in the process. Some posts on the Internet are the same. I feel that everyone is copying and pasting and then publishing directly. I have summarized the pitfalls and solutions encountered in the process. I hope this blog can help you. At the same ...
Posted by Unholy Prayer on Thu, 28 Apr 2022 10:20:45 +0300
Take a look at the catalog first
Imagine such a scenario: Nginx loads two Tomcat s, so it is very troublesome to check the log. Each time you check the log, you have to log in to two servers and search one by one. Two are OK. What if five? What about 10? It's hard to view logs, so we need a log collection system to centrally mana ...
Posted by pixelfish on Wed, 27 Apr 2022 09:44:33 +0300
maxwell synchronize incremental data
Maxwell will monitor the data change operations of Mysql database in real time (including insert, update and delete), and send the changed data to Kafka, Kinesi and other stream data processing platforms in JSON format.
Maxwell's working principle is to read the binary log of MySQL database i ...
When Apache NiFi is used to distribute the enterprise master data to the downstream business system in real time, the downstream systems include MySQL, PostgreSQL, Oracle and other business systems. Among them, NiFi does not directly support Oracle Upsert semantics, resulting in a large number of updates to the master data of products, ...
Posted by betportal on Tue, 26 Apr 2022 01:25:01 +0300
HDFS core source code analysis
Hadoop source code compilationHDFS source code structure analysisHDFS core source code analysis
Master the scene of compiling source codeMaster Hadoop source code and compile it on Linux platformUnderstand the compilation of Hadoop source code on Windows platformUnderstand the sou ...
Posted by cesar_ser on Tue, 26 Apr 2022 00:32:06 +0300
ClickHouse From Beginning to Proficiency (3)
Explain View Execution Plan
To view the execution plan of an sql statement before Clickhouse version 20.6, you need to set the log level to trace in order to see it, and you can only actually execute sql and view it in the execution log. Native execution plan syntax was int ...
Posted by Harbinger on Mon, 25 Apr 2022 19:06:16 +0300
Maximum matching method: maximum matching refers to taking the longest word in the dictionary as the scanning string of the first number of words based on the dictionary and scanning in the dictionary (in order to improve the scanning efficiency, multiple dictionaries can also be designed according to the number of words, and then scanning from ...