lsp association

The "Downwind View", a daily issue, gives the quickest and most exclusive view of the hottest topics and the most noteworthy focus and events. August 21 morning, by the Chinese Internet Association launched the first "blog service Self-discipline Convention" officially released in Beijing, the Daily Network, Sina, Sohu, NetEase, Tencent, Thousand Dragon Net, more than 10 blog service providers signed the Convention. After the publication of the Conven

Often see some of the recommendations of the Hive optimization that when the small table with the large table to do the association, the small table written in front, so that can make the association of Hive Faster, the reason is said because the small table can be put into memory, and then the big table each record to go in memory, and finally complete the correlation query. The reason for this seems reaso

interface. iii. Dependency Relationshipsimply understood, dependency is that a class A uses another Class B, which is accidental, temporary, and very weak, but changes in class B affect Class A. For example, if someone wants to cross the river, they need to borrow a boat, and the relationship between the man and the ship is dependent. At the code level, for Class B as a parameter, Class A is used in a method.In UML class diagram design, a dependency relationship is represented by a dashed line

Association Analysis, also known as association mining, is to search for frequent patterns, associations, correlations, or causal structures between project sets or object sets in transaction data, relational data, or other information carriers. A typical example of association analysis is basket analysis. Analyzes customers' purchasing habits by finding the rela

triangle. • During code implementation, the Object-oriented Inheritance mechanism is used to implement generalized relationships. For example, the extends keyword is used in Java and the colon is used in C ++/C #:. public class Person { protected String name; protected int age; public void move() { …… } public void say() { …… }}public class Student extends Person { private String studentNo; public void study() { …… }} In UML, there

I have been studying design patterns for a long time, but I still have little idea about several types of UML relationships. If these relationships are not fully understood, they will directly affect the understanding of the relationships between class charts. Let's analyze the relationships below! Relationships between classes 1. Dependency (dependency), relization (implementation), and generalization (generalization) 2. Association (

The relationship between classes indicates the strong relationship between classes, and dependency indicates the weak relationship between classes; From the point of view of the time between classes, Association indicates the "persistent" Relationship between classes. This relationship generally indicates an important relationship between businesses and needs to be saved, or "persistence" is required, or it needs to be stored in the database. For exa

models, such as Bayesian, time series, and association rules, are common models. Different model algorithms can be applied based on different problem features. For example, the product recommendation mentioned in this article is typically suitable for solving with association rules. The typical beer and diapers problems in data mining are basically based on this method. Create a Mining Model Project Note:

There are two ways to map to one to each: Primary key association and foreign Key Association1. A primary key association is a one-to-one association that references the primary key of another table1. Because of the primary key correlation, the primary key values of the associated records of the two tables associated with the primary key must be kept in sync. Thi

The essence of an association relationship is to map an association relationship to a database. An association relationship is embodied in the object model as one or more references in memory. One-to-many Relationship: A one-to-many relationship is divided into "one-way one-to-many/many-to-many relationship" and "two-way many-to-many" relationship. • "One-way one

InheritedRefers to a class or interface that inherits another class or interface and can add its own new functionality.RealizeRefers to a class that implements the interface interface.DependentSimply put, the method in one class uses another class, and the general dependency in Java is either a local variable, a formal parameter to a method, or a call to a static method. is a weak relationship. For example, when a person writes with a pen, the relationship between a person and a pen is dependent

"Hibernate" About one-way, bidirectional Association mappingsFirst we look at Hibernate's official explanation for one-to-one unidirectional association:The one-way and one-way associations based on the foreign Key association are almost the same as the unidirectional many-to-one association. The only difference is a one-way off.The Foreign key field in the union

"Hibernate" About one-way, bidirectional Association mappingsFirst we look at Hibernate's official explanation for one-to-one unidirectional association:The one-way and one-way associations based on the foreign Key association are almost the same as the unidirectional many-to-one association. The only difference is a one-way off.The Foreign key field in the union

Reprint Please specify source: http://blog.csdn.net/guolin_blog/article/details/39207945Now that we have a certain understanding of the usage of Litepal and learned how to use Litepal to create tables and upgrade tables, let's move on to the advanced level today and explore how to use Litepal to establish the association between tables. Friends who have not read the previous article suggested first refer to the Android database Master cheats (iii)--Us