object-oriented-database

问题 Background: Okay, so I'm looking for what I guess is an object database. However, the (admittedly few) object databases that I've looked at have been simple persistence layers, and not full-blown DBMSs. I don't know if what I'm looking for is even considered an object database, so really any help in pointing me in the right direction would be very appreciated. I don't want to give you two pages describing what I'm looking for so I'll use an example to illustrate my point. Let's say I have a

问题 I wonder how Object Oriented data modeling is different from Object Relational data modeling? Is it something like the pluses of both object oriented and relational data modeling were clubbed to achieve object relational data modeling? cheers 回答1: Object-Relational data modeling supports some object-oriented concepts, while still supporting some relational concepts: Inheritance -- one table can have an IS-A relationship with another table. Likewise custom data types support inheritance.

问题 As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance. Closed 8 years ago . I am pretty new to programming(just finished University). I have been thought in the last 4 years about Object Oriented development

问题 I've done lots and lots of code in PHP that is object-oriented, but up until now, all of my classes have been, "singular", I suppose you can call it. I am in the process of changing several classes (that have 5 or so identical methods) to extend one class (to rid myself of duplicate code). I am running into a few issues. I am trying to access a method in a parent class, but you can see the issue. Parent class: class DatabaseObject { public static function find_all() { return self::find_by_sql

问题 I've done lots and lots of code in PHP that is object-oriented, but up until now, all of my classes have been, "singular", I suppose you can call it. I am in the process of changing several classes (that have 5 or so identical methods) to extend one class (to rid myself of duplicate code). I am running into a few issues. I am trying to access a method in a parent class, but you can see the issue. Parent class: class DatabaseObject { public static function find_all() { return self::find_by_sql

问题 I'm a very beginner on DB designing and I need to create a DB for a project. I can explain what I wanna do in Object Oriented terms and thankfully a DB expert would be kind enough to explain me how I can deal with this in a DB aspect . I wanna create a User (Id, Name) entity that would have a relation with a Location entity (state, city). So in programming language i would like to have the following class User { String Name; Int Id; Location location; } class Location { String State; String

问题 I don't know if this is the right title for this question. Anyway, recently I have heard about that you could make life easier when creating database. By in which you use object based database. It will make migration to other type of database also easier e.g. from MySQL to SQLlite or something else. Anyway the main way I do a webpage with database access now is that I manually write down the Query to fetch what I need from a database. However it can be done in some other way also which does

问题 What is the difference between graph-based databases (http://neo4j.org/) and object-oriented databases (http://www.db4o.com/)? 回答1: I'd answer this differently: object and graph databases operate on two different levels of abstraction. An object database's main data elements are objects, the way we know them from an object-oriented programming language. A graph database's main data elements are nodes and edges. An object database does not have the notion of a (bidirectional) edge between two

问题 I am curious about using an object db so thought i'd give Eloquera a go. I am having problems getting it running unfortunately. (running in "desktop mode") I have done these steps as directed: 1) Copy the following assemblies and a configuration file from the %ProgramFiles%\Eloquera folder into a project folder: Eloquera.config Eloquera.Client.dll Eloquera.Common.dll Eloquera.Server.exe You can copy the reference files into a separate folder for your convenience. 2) Uninstall the Eloquera DB

问题 Please help me understand further the many to many relationship. Suppose I have Teacher and Students Table and in my understanding it is one-to- many . Teacher TeacherId Primary Key TeacherName Student StudentId Primary Key TeacherId Foreign Key StudentName TeacherId can appear several times in the Student Table. I'm confused because Student can have many teacher. When can I say something is one-to-many and when is it many to many ? I can say One Student can have many teacher. On the other