Original link Address: http://www.transwarp.cn/news/detail?id=173
ETL is an important link in building data Warehouse. Through this process the user extracts the required data and imports the data warehouse according to the defined model. Because ETL is the necessary process of building data Warehouse, its efficiency will affect the construction of the whole data warehouse, so its effective
,1040w records, data table structure: hive> desc order_sight;
OK
create_time string none
ID string none
order_id String Third, analysis3.1 Where ConditionThen we would like to see the area ID is 9718, the date is the 2015-10-10 all order ID, then SQL needs to write as follows: where s.id='2015-10-10' The time required is 52 seconds, if we change the way SQL is written:
Believe that in the process of ETL inevitable practical union all to assemble the data, then this involves whether the problem of parallel processing.Whether a parallel map is applicable in hive can be set by parameters:set hive.exec.parallel=trueThen it is useful for the data of the previous blog, Link: http://www.cnblogs.com/liqiu/p/4873238.htmlIf we need some data:Select from (Selectfrom where create_time="2015-10-10"9718 Select as from where 97
Tags: implementation mechanism originally page organizes tables based on free article content index ClustFollowing the book on SQL tuning (SQL tuning or SQL optimization) in the essentials of high-performance SQL tuning and case resolution, we talk today about one of the most important core mechanisms of SQL
Tags: and fast speaking tuning market buffer way a completely"High-performance SQL Tuning essentials and Case Resolution" a book has been launched, many enthusiastic readers on the contents of the book and some of the specific questions raised questions, because of the numerous readers plus my daily work busy, here on the SQL
timeout; b read timeout; c write timeout);2.2. Parallelization of the serial request;A) use of curl_multi_* ();b) Use the swoole extension.
3. compress the PHP interface output:Using gzip compressionBenefits: Facilitates faster reception of data by client side;Cons: Extra CPU overhead
4. Cache Duplicate content: multiple requests, the content is not changed under the circumstances;
5.smarty Tuning and time window overlap ideas (which can be used in c
FineReport performance tuning methods, finereport Performance TuningThe basic idea of FineReport performance optimization is to properly set the memory size of the application server.
Generally, the default memory configuration of the server is relatively small. In larger application projects, this memory is not enough
Need for Performance Tuning
In this world of SAP programming, ABAP is the universal language. in most of the projects, the focus is on getting a team of ABAP programmers as soon as possible, handing over the technical specifications to them and asking them to church n out of the ABAP programs within the "given deadlines ".
Often due to this pressure of schedules and deliveries, the main focus of m
GIS image cutting performance tuning and GIS image Performance TuningStatus Quo and objectives
DellR920 Server, virtualized vmware vsphere 5.5 system, Guest System Windows Server 2012 R2. Deploy software ARCGIS 10. Image graph cutting test: the original cut takes 70 hours, And now it takes 17 hours. There is still room for further optimization. Debugging objectiv
I will share 11 practical tips on Java performance tuning and java Tuning
Most developers think that performance optimization is a complicated problem and requires a lot of experience and knowledge. Yes, it is not wrong. It is not easy to optimize the application to achieve the best
A basic knowledge
1.1 What is the performance
Before performance tuning, let's first look at what performance is. As for performance, I think everyone who has studied Java can list a few points or even talk about it. In the book "Java TM Platform
SQL Server Performance Tuning methodology and common tools, SQL Server Tuning
In earlier articles, we mentioned the DETECT methodology in Performance Tuning. Here we will briefly review the DETECT methodology.
Discover the problem: found the problem
Lead e the conditions: E
Linux server performance tuning skills, linux Server TuningPerformance tuning skills for 20 Linux servers
Guide
Linux is an open-source operating system that supports various hardware platforms. Linux servers are world-renowned. The main difference between Linux and Windows is that, by default, a Linux server does not provide a GUI (graphical user int
. Net Performance Tuning Series
Article
Index of series articles
. Net Performance Tuning: Use of ants performance profiler
. NET performance optimization 2: Use Visual Studio for code measurement
. Net
I. Preface
Index plays an important role in database performance. The advantages and disadvantages of index design directly affect the efficiency of DB execution. Therefore, when performing DB tuning, some of them will start to process the index. SQL server also provides a good tool for Database Engine Tuning Advisor and provides some advice on index creation and
MySQL performance tuning and Architecture Design-Chapter 1 Basic Principles of scalable design, mysql Tuning
Chapter 1 Basic Principles of scalable design Preface: With the rapid increase of information, the development of hardware equipment has gradually become unable to keep up with the application system's requirements for processing capabilities. How can we s
thickness of the arrow lines indicates the amount of data. In a graphical execution plan, each of the different operators has its own property values, and we can move the mouse over the operator icon to view Of course, you can also right-click on the icon, view the properties, go to the Properties panel and view more detailed property values The detailed indicator values for each operator in this case are described later, but there are a few key values here, which can be said to mention a lit
MySql performance tuning policy and mysql tuning policy
This topic provides detailed parameter descriptions for my. cnf configuration.
The sample configuration is as follows:
# Cat my. cnf
# MySQL client library initialization.
[Client]
Port
= 3306
Socket =/tmp/mysql. sock
Character-set-server = utf8
# The MySQL server
[Mysqld]
Init_connect = 'set na
The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion;
products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the
content of the page makes you feel confusing, please write us an email, we will handle the problem
within 5 days after receiving your email.
If you find any instances of plagiarism from the community, please send an email to:
info-contact@alibabacloud.com
and provide relevant evidence. A staff member will contact you within 5 working days.