I\'d like to understand the exact semantics of using \"FOR UPDATE\" in connection with \"JOIN\". Does it just lock all the rows that were effectively used to build the end result? Does it do something
I was building a feed system ala facebook just for the fun and training of it but I came up with an interesting problem. Imagine this scenario:
TL;DR what\'s the best way to migrate lots of data between one very poorly structured database (with much repetition of columns, no interrelations, and duplicate data), to another highly organised and
I\'m learning some ADO.NET. I noticed quite a few Database functionality can also be found in ADO.NET.
I\'ve come up with two approaches to the same idea and would like to avoid any obvious pitfalls by using one over the other.I have a table (tbl_post) where a single row can have many relationships to
I\'ve seen certain object-oriented experts advise that domain objects (POCOs) should be immutable. That is, their state should be entirely determined at construction, and changes to state should requ
The system rules: Departments can have 0 to many divisions. A division must belong to only one department.
In a database that stores tournaments I have this relational structure to store matches and their games:
This is most likely a very basic question, but nevertheless: Basically the User ent开发者_如何学JAVAity has an Id and a privilege enum.
I ha开发者_StackOverflow中文版ve a problem understanding how to set up the ActiveRecord relationships correctly for the following scenarios...
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