what is data deduplication

When I use mysqldump to export a portion of the table data, what is the case? When I use mysqldump to export a portion of the table data, what is the case? There were 2000 records, which were exported to 1800 and 200 fewer records

Here's what the code does today: 1. Read data from a database 2. Determine the value and process the following business logic based on the result of the decision Step1: Field read from database: Table $table_name, ID field data type is int Select Id from $table _name $id = $value [' id ']; Step2: Judgment Value:

1. What is meta dataThe data in any file system is divided into data and meta data. Data refers to the actual data in the normal file, while

What is Bloom Filter] Bloom Filter is a space-efficient random data structure. It uses a bit array to easily represent a set and determines whether an element belongs to the set. The efficiency of the Bloom Filter has a certain price: when determining whether an element belongs to a set, it

Ask for php, a socket expert, and check what type of data format I sent in hexadecimal format, however, the packet capture tool does not know what type of data format it translates into. see the shadow in the figure. ------ solution -------------------- hexadecimal php, socket expert, see

based on target response probability supported by data mining, focusing on product function optimization, target user segmentation, Activity (copywriting), channel optimization, cost control, etc.) theory Probability (probability): marketing, operations with probability as the core, the pursuit of refinement and accuracy rate Product (product): Focus on the function of products, emphasizing the product selling point Prospects (consum

1. Definition of a transaction Transactions provide a way to group T-SQL statements so that they can be treated as a unit: All statements in a group are executed, or none are executed. A transaction is a mechanism that ensures that a collection of one or more SQL statements is not treated as a single unit of work, and SQL Server automatically modifies all data-

Let's take a look at the data format vip.stock.finance.sina.com. cnqviewnewSinaHy. php: I obtained the Sina stock data nbsp; from this address and returned the following: var nbsp; S_Finance_bankuai_sinaindustry nbsp; {new_blhy: new_blhy, let's see what format the data is

I received a lot of data from the front-end, such as A1, B1, A2, and B2... the properties of A (time) and B (content) are the same. in the database, I only want to use A text field to store it. Therefore, they need to be separated by characters, split the string when using it, but I don't know what character to use. I am afraid of this... I received a lot of data

Why is the data always inserted? This post was last edited by YXQC on 2014-05-05 14:20:32 From one database to another, there are 8 million data in the table. while ($mssql _row = Mssql_fetch_array ($rs)) $MID = $mssql _row[0]; $sql = "INSERT into Flow01 (TDM,) VALUES (' $TDM ',)"; mysql_query ($sql); And the ID of the inserted table

Data type confusion: what is an int (11 )?, Confusionint Http://everythingmysql.ning.com/profiles/blogs/data-type-confusion-what-is-an Over and over I see MERs that don't understand whatint(11)Really means. Their confusion

A large number of IP addresses are required when addressing mobile data services. The current public IPv4 address has become a scarce resource, so mobile data operators are faced with the problem of choosing the address between IPV6 and private IPv4 addresses. At present, the industry generally believe that the 3G should be used IPV6 address. In addition, the choice of IPV6

first of all, what is an escape character? The escape character, in fact, is the specified PHP syntax with "\" to output. However, the syntax of the rules in different systems to transfer the role of the character is different, for example: in the Windows System carriage return line character with "\ r" or "\ n", an

memoryComparison between string and stringbuffer efficiencyIn some special cases, the string object will not change at a slower rate than the StringBuffer object, especially in the following string object generation, where string efficiency is far faster than StringBuffer:String"hello ""world"new"hello ""world" );You'll be surprised to find that the speed at which the string object was generated was simply too fast, and at this time StringBuffer had

What is the data type of a variableIn variables, because the variables occupy a different space unit (the site size is not the same), but also divided into several data types, like the supermarket packaging bags, there are several different types of goods, different products