Tag：efficiency
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Time：2021-2-22
data compression Many small files, small files compressed into a large file, IO efficiency Bzip2 LZO Snappy Profile tuning
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Time：2021-2-8
Activity background Nowadays, great changes are taking place in the field of software development and operation and maintenance. In order to cope with the rapid changes in business, enterprises have accelerated the pace of digital transformation. This technology salon with the theme of “Devops transformation and landing practice” is hosted by Devops community in China. […]
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Time：2021-2-5
Modern programmers, no matter the front-end, mobile end, back-end or even some UI and products are heavy users of GitHub. In product design, architecture design, technology selection, looking for technical solutions for a specific function and other scenarios, GitHub is a good channel. Indeed, in many cases, you can find wheels made by others to […]
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Time：2021-2-2
The following test table has no data, and the dept table has data. Select directly, there will be data set. The exists of PLSQL is used to judge whether a subquery has a result set returned. As long as the result set of a subquery has data, the exists is judged to be […]
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Time：2021-2-1
background The cause of the incident lies in the boss’s two recent “breakdowns”, one last year’s and one recent. The common reason is that scaffolding makes mistakes when publishing and packaging on the publishing platform, resulting in the white screen of online applications not available. The most amazing thing is that after several code reviews, […]
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Time：2021-1-30
The emergence of index is to improve query efficiency, but there are many ways to achieve index, so the concept of index model is introduced here. There are many data structures that can be used to improve the efficiency of reading and writing. There are three common and relatively simple data structures: hash table, ordered […]
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Time：2021-1-23
There are many ways for go language to operate files. The most common, for example, is to modify the file itself directlyReadandWriteIn addition, you can usebufioIf the file is small, use theioutilIt’s also a way. Faced with so many file processing methods, beginners may be confused: which one should I use? What’s the difference between […]
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Time：2021-1-20
This article is updated on August 18, 2019, using MySQL 5.7 and operating system deepin 15.4. catalog Data type of optimization table Improve the efficiency of table access by splitting Inverse normalization Using intermediate table to improve the efficiency of statistical query Once the database object is designed and put into use, it is troublesome […]
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Time：2021-1-8
As we all know, the efficiency of like is very low. If there is a large amount of data, it will be very slow. Today, we found a built-in function instr() which is more efficient than like SELECT * FROM msg_ List where title like ‘ Can be replaced by: SELECT * FROM msg_ List […]
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Time：2021-1-5
How to view SQL execution plan UsePL/SQLThe specific usage is as follows: newly buildExplain the plan window, willSQLCopy in to execute, and the execution plan will be displayed. SelectSQLStatement, click menutool–Explain the planOr press the shortcut keyF5 Implementation plan result description Table scan table access by index rowid Through ROWID’s table access, I / O […]
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Time：2021-1-3
1 set overview There are many collection classes in Java, such as ArrayList, LinkedList, HashMap, treemap, etc. The function of a collection is to hold multiple objects. They are just like containers (in fact, it’s OK to call them containers directly. That’s what C + + calls them). When you need them, you can take […]
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Time：2020-12-14
Minglue technology is a leading provider of data platform and enterprise intelligent decision-making platform in China. It is committed to promoting the digital transformation of large and medium-sized enterprises with high knowledge and management complexity through big data analysis and mining and cognitive intelligence technology. At present, minglue technology has provided data intelligence solutions for […]
