what is star schema in data warehouse

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

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

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

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

Ask the data returned by json for an inexplicable explanation. what is the preceding table? send a json file Request File Category. php Corresponding tables in the database Json result The data results contain a number of table data (emoticons]

Look at the online data with the text type effect efficiency What type of field is it used for? Save graphic format Reply content: Look at the online data with the text type effect efficiency What type of field is it used f

What is the relationship between the data table and the controller and the Model in ThinkPHP? what is the relationship between the data table and the controller and the Model in ThinkPHP? Reply to discussion (solution) Go thro

Php+mysql what is the fastest way to update millions data? Reply content: Php+mysql what is the fastest way to update millions data? InnoDB Read Detach Chaizi section to make redundant table Cache to do merge upda

What is the data format? A: 24: {s: 8: duration; I: 900; s: 8: redoable; s: 2: 20; s: 8: onebyone; s: 1: 0; s: 7: answers; s: 1: 1; s: 13: given_answers; s: 1: 1; s: 17: shuffle_questions; s: 1: 1; s: 15: shuff what is the data fo

How to judge what the file_get_contents data is encoded Title ------Solution-------------------- EUC-CN is the most commonly used representation of GB 2312. The "GB2312" on the browser encoding table is usually referred to as "EUC-CN" notation. But you can't get the righ

Php Using PHP to read the TXT file data (words, phonetic transcription and translation) to another TXT file, garbled, what is the reason? Reply to discussion (solution) Of course because the coding is inconsistent. How to solve it?Of course because the coding is incons