I would appreciate some help with an SQL statement I really can\'t get my head around. What I want to do is fairly simple, I need to take the values from two different tables and copy them into an ma
A Post belongs_to a User, and a User has_many Posts. A Post also belongs_to a Topic, and a Topic has_many Posts.
I am currently using MS SQL Server 2008 but I\'m not sure it it is the best system for this particular task.
We\'re drawing up the database structure with the help of mySQL Workbench for a new app and the number of joins required to make a listing of the data is increasing drastically as the many-to-many开发
Is it possible to break the composite key 开发者_JAVA百科of a table and use one of them as a primary key for other table? If yes, then please tell me how can I do it?Generally you use a composite key
I have this problem decomposing a relation schema into a set of开发者_高级运维 schemas that are in 3NF.
Suppose you have two sets of conceptual entities: MarketPriceDataSet which has multiple ForwardPriceEntries
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Is it possible to listen to relation database update? For example, my web app want to send data update to client through Comet technology. I can have the program to poll the database periodically, but
I\'m currently using the following PHP code: // Get all subordinates $subords = array(); $supervisorID = $this->session->userdata(\'supervisor_id\');
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