On the theoretical concept of slowly changing Dimension slowly changing dimension see Data Warehouse Series-Slow slowly changing dimension (slowly changing Dimension) common three types and prototype design
This article summarizes several ways to realize the slow gradual change di
Prompt: The explanation in this article is more profound. You need to read it with a calm mind!
Preface
At the bottom layer of the IOS interaction model, there is a concept of "space" (specifically, the IOS Space Model), and the most basic attribute of space is three dimensions. Slide depends on the two-dimensional environment of the screen. You can also think about it from the Dimension Perspective. The most common slide operation is to delete short
Introduction
Fact table
The foreign key that stores the measurement value and dimension table.
Dimension Table
Angle and category. Time, region, and status.
Old Method
Select * from order oinner join district d on o. discode = d. discodeinner join address a on o. addressid =. addressidwhere o. createdate> '2014-2-5 'and o. createdate
It is difficult to add conditions when the stored procedure is killed.
1. Overview of dynamic arrays with any deformation of dimensions and lengthsRecently, some colleagues have to design a multidimensional array that can be freely deformed. After a few days of hard work, they have to solve the problem and turn to me for help. So I wrote an array ADT that can freely change the dimension and length. Later, I thought that someone on the Internet should also need this kind of things. Why don't I put it on my blog and let fr
One of the previous articles-the Data warehouse multidimensional data model already provides a brief description of the definition and structure of an overly-dimensional model, as well as the concept of the fact table and the dimension table (Dimension table). Multidimensional data model, as a new logical model, gives the new organization and storage form of data, and the advantage of the analysis is the ef
Tensorflow obtains the variable dimension information.
Tensorflow version 1.4
Getting a variable dimension is a frequently used operation. You can use the following operations to obtain a variable dimension in tensorflow:
Tensor. shape
Tensor. get_shape ()
Tf. shape (input, name = None, out_type = tf. int32)
Perform A simple analysis on the above three o
array element
3. Reference of one-dimensional array elements
The reference method of array elements is as follows:
ArrayName [index]
Index is an array subscript, which can be an integer constant or expression. The subscript starts from 0. Each array has an attribute length to specify its length. For example, intArray. length indicates the length of the array intArray.
Multi-dimensional array
In Java, multi-dimensional arrays are considered as arrays of arrays.
1. Two-dimensional array Definitio
Designers in the drawing of some simple three-dimensional graphics, usually need to mark the processing size, such as furniture, shelves and other simple three-dimensional graphics. See a lot of friends are not in the CAD to mark the size, but in the CAD to draw the figure after the print out, with a pen and then mark the size. Today we are in the CAD for a simple shelf three-dimensional graphics dimensioning, for friends as a reference.
There is no three-dimensional annotation function in Auto
1 definition of the VC dimensionVC dimension is actually the sample capacity before the first break point. The standard definition is: For a hypothetical space, if there are n samples can be assumed in the space of the H by all possible 2 of the n-th form of separation, it is said that the hypothetical space can be divided into n samples, assuming that the space VC is the maximum number of samples it can be scattered n. If any number of samples have f
In Oracle Data Warehouse (OLAP), MVIEW, Query Rewrite, and Dimension are very important optimization methods, I don't want to repeat the previous two here, mainly to experience the role of dimension. To play the role of a dimension, we still need to use the previous two. below is the simplest example of a dimension tab
experience and insights, but also let me have some different thinking about operation.
I think the shift in operational dimension is far more valuable than the mere lifting of operational technology.
I think that, in a research and development team, to remove the business requirements to achieve the level of things, the other is the scope of operations, this category of things in essence is in the software lifecycle of the operation of the maintenan
VC Dimension (
Vapnik-Chervonenkis dimension) Is an important indicator of function set learning performance defined by statistical learning theory to study the speed and promotion of consistent convergence in the learning process. The traditional definition is: For an indicator function set, if H samples exist, functions in the function set can be separated by all possible forms of K power of 2, the functi
An important difference between multidimensional data and two-dimensional data in common relational databases is that there are some additional
Dimension, that is, adding more conditions to data display. Therefore, the dimension concept in a multi-dimensional dataset is
It is very important that we have recently reached the Data Warehouse. It may be said that the data mart is more spec
Some people often ask a question: do fact tables and dimension tables must be in a database? Why is there such a problem? As we mentioned, if the data warehouse is large enough, it may be split into so-called data mart. Generally, the division is based on the so-called different business modules, such as personnel management, sales management, and financial management.
Some people often ask a question: do fact tables and
Feature Selection (Dimension Reduction) is an important step in data preprocessing. For classification, feature selection can select the features most important to classification from a large number of features to remove noise from the original data. Principal Component Analysis (PCA) and linear discriminant analysis (LDA) are two of the most common feature selection algorithms. For more information about PCA, see my other blog. Here we mainly introdu
(1) Create aliases (table-new Object-alias) in the physical layer for the table(1) Create dimensions in the Business layer (table-Create logical dimension--"dimension based on level hierarchy")Drillthrough is the function of the dimension itselfGeneral information in the name: departmentKeyword action: Determining unique values and determining what to displayAggr
Incorrect array dimension returned by PHP for retrieving Webservice data I used the nusoap plug-in to read webservice, but an error occurred. When the returned array is greater than one group, the returned value is correct. However, when only one group of array data is returned, the dimension changes, resulting in incorrect array length obtained by count. The code is as follows: when there are two groups of
Incorrect array dimension returned by PHP for retrieving Webservice data I used the nusoap plug-in to read webservice, but an error occurred. When the returned array is greater than one group, the returned value is correct. However, when only one group of array data is returned, the dimension changes, resulting in incorrect array length obtained by count. The code is as follows: when there are two groups of
One-dimensional array is used as two-dimensional, and dimension array is used as two-dimensional# Include Int main (void){Int I, j;Int a [] = {, 35 };Typedef int (* Type) [5];Type B = (Type);For (I = 0; I {For (j = 0; j Printf ("% d", B [I] [j]);Printf ("\ n ");}
Return 0;
}
What is access to a two-dimensional array using a one-dimensional array? What should I do if y (4) and y (2, 1) are the same variables?
This is what LZ can look.Data storage is
In the process of extracting data from an OLTP business database to a DW data warehouse, especially after the first import, the problem is that some data in the business database has been changed to reflect these changes to the Data warehouse. In the Data warehouse, which data should be changed, which can not be changed? With these changes in mind, the dimension tables in the Data warehouse should be designed to meet these needs.
It is clear that the
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.