deduplication application

Hadoop written questions: Identify common friends of different people (consider data deduplication) Example: Zhang San: John Doe, Harry, Zhao Liu John Doe: Zhang San, tianqi, Harry The actual work, the data to reuse is still quite a lot of, including the empty value of the filter and so on, this article on data deduplication and inverted index detailed explanation. first, data

occasions, including online data, nearline data, and offline data storage systems, it can be implemented in the file system, Volume Manager, NAS, and San. Dedupe can also use data transmission and synchronization as a data compression technology that can be used for data packaging. Why is the most successful application of dedupe Technology in the Data Backup field, but few applications in other fields? This is mainly determined by two reasons: first

Python list deduplication method you should know, python list deduplication Method Preface List deduplication is a common problem when writing Python scripts, because no matter where the source data comes from, when we convert it into a list, the expected results may not be our final results, the most common thing is that the Meta in the list is repeated. At this

Disable Windows deduplication and windows deduplication Deduplication can reduce disk usage, but improper use may also increase IO. In addition, this function also blocks the hard disk. Therefore, when the hard disk usage is high, it is also difficult to fragment, So you sometimes need to disable the deduplication fun

This article mainly introduces the sample code for de-duplication and de-duplication of JS arrays. If you need it, you can refer to it for help. Method 1: deduplication The Code is as follows: ScriptArray. prototype. distinct = function (){Var a = [], B = [];For (var prop in this ){Var d = this [prop];If (d = a [prop]) continue; // prevents loops to prototypeIf (B [d]! = 1 ){A. push (d );B [d] = 1;}}Return;}Var x = ['A', 'B', 'C', 'D', 'B', 'A', 'A',

Array deduplication Array, Array deduplication Array var aee3=[31,42,13,19,5,11,8,13,40,39,1,8,44,15,3]; Array.prototype.unqu2=function(){ this.sort(); var arr2=[this[0]]; for (var j = 1; j There are a lot of de-duplication methods on the Internet, and the most stupid is the second method, and the best efficiency is the third one.

Simple example of php array deduplication (one-dimensional and two-dimensional array deduplication) $ Aa = array ("apple", "banana", "pear", "apple", "wail", "watermalon "); $ Bb = array_unique ($ aa ); Print_r ($ bb ); ?> Output result: Array ([0] => apple [1] => banana [2] => pear [4] => wail [5] => watermalon ).2. duplicate items of two-dimensional PHP

PHP two-dimensional array deduplication algorithm, PHP two-dimensional array deduplication Algorithm Requirement The following two-dimensional array is available: Array (8) {[0] => array (2) {["name"] => string (4) "name" ["value"] => string (6) "qingye"} [1] => array (2) {["name"] => string (5) "phone" ["value"] => string (11) "13812341234"} [2] => array (2) {["name"] => string (12) "fileds_507 []" ["value

of deduplication is generally used for some applications.ProgramFor example, exchangeserver, because the application knows the data it manages, it can easily remove it internally. Zfs provides block-level deduplication technology, which is more suitable for general scenarios. Zfs uses sha256 to calculate the hash signature. When can I remove duplicates?

I. Planning the deployment goalsData deduplication for Windows 8.1server 2012 is designed to be installed on the primary data volume without adding any additional dedicated hardware. This means that you can install and use the feature without affecting the primary workload on the server. The default is non-invasive because they allow the data "lifetime" to reach five days before a particular file is processed, and the default minimum file size is up t

Hyper-V Server data deduplication technologySwaiiow heard that the new technology in Windows Server 2012 is called Deduplication, which is said to save disk space significantly, and let's look at what deduplication is:Data deduplication refers to finding and deleting duplicates in the data without affecting their fidel

the data storage process. Second, different data blocks may have the same fingerprint. In practical applications, the SHA1 HASH algorithm is usually used to calculate the fingerprint, but there may be a HASH conflict event. If this conflict is not solved, it will cause data loss to the application. Again, after the fingerprint computation is complete, you also need to find whether the data block with the same fingerprint exists in the system. For lar

Q: What are the advantages and disadvantages of the software-based deduplication and hardware-based deduplication products? A: software-based deduplication aims to eliminate source redundancy, while hardware-based deduplication emphasizes data reduction of the storage system. Although bandwidth compensation cannot

In Windows 2012, you can enable data deduplication for non-system volumes. Deduplication optimizes volume storage by locating redundant data in the volume, and then ensuring that the data is saved in only one copy of the volume. This is accomplished by storing the data in a single location and providing this location reference for other redundant copies of the data. Since data is divided into 32-128kb chunk

Label:Let's say we have a MongoDB collection, take this simple set as an example, we need to include how many different mobile phone numbers in the collection, the first thought is to use the DISTINCT keyword, db.tokencaller.distinct (' Caller '). Length If you want to see specific and different phone numbers, then you can omit the length property, since db.tokencaller.distinct (' Caller ') returns an array of all the mobile phone numbers. but is this a way of satisfying all things? Not

research on high performance data deduplication and detection and deletion technologyHere are some fragmentary data about the re-deletion of things, previously summarized, put on can communicate with you.The explosion of 1 data volumes brings new challenges to the capacity, throughput performance, scalability, reliability, security, maintainability, and Energy management of existing storage systems, eliminating redundant information and optimizing sto

Reading: deduplicationThe emergence of technology has a certain source, so we should start from the beginning. Although the current price of storage media has plummeted, the Unit storage cost is already very low. But it still cannot keep up with the growth rate of enterprise data files. As a result, energy consumption, data backup management, and so on have become difficult issues. In addition, some duplicate files also increase. To this end, enterprises urgently need a technology to ensure that

INSERT into table (ID, name, age) VALUES (1, "A", +) on duplicate key update name=values (name), Age=values (age)/* Insert Data: If there are duplicates, select Update; */Insert ignore into ' testtable ' (' Mpass ', ' Pass ') select Mpass,pass from Rr_pass_0 limit 0,1000000replace into ' testtable ' ( ' Mpass ', ' Pass ') select Mpass,pass from Rr_pass_0 limit 0,10Set PRIMARY key: Discard if duplicate data is selected;SELECT *, COUNT (distinct name) from the table group by nameQuerying for dupli

Tags: where div from greater than equals join AC Max ack reservedQuery for the number of elements not repeatingElements in the query table with a number of elements greater than or equal to 2SELECT goods_id,goods_name from Tdb_goods GROUP by Goods_name have COUNT (goods_name) >=2; Then use the left join to connect the original table with the above query results, delete duplicate records, and keep records with smaller IDsIf you want to keep the same ID for the larger, as shown belowDELETE T1 fro

Function descriptionData deduplication refers to finding and deleting duplicates in the data without affecting their fidelity or integrity. The goal is to change (32-128 KB) small chunks by splitting the files into sizes, identify duplicate chunks, and then keep a copy of each chunk to store more data in a smaller space. A redundant copy of a chunk is replaced by a reference to a single copy. Chunks are compressed and then organized into the System Vo