I\'ve been wondering lately. Lets say we\'re doing a webapp with JSF+Spring+JPA/Hibernate (or well any other technologies) and lets say we have a \"User\" entity. We want the User to have a unique log
A top class called Parametric is used to create objects which can have parameters associated with them:
I have rows in an Oracle database table which should be unique for a combination of two fields but the unique constrain is not set up on the table so I need to find all rows which violate the constrai
i have an entity that contains two other entities with @ManyT开发者_开发知识库oOne relationship.
I have a field with an unique constraint: @Column(unique=true) private String uriTitle; When I try to save two entities with the same value, I get an exception - but another exception than I execte
Below is the use case: I have a unique index defined on 3 columns say A,B,C. Assume the values in them are A1,B1,C开发者_StackOverflow1.
I have add开发者_如何学编程ed an index on a table just to ensure that a set of fields together form a composite unique key (Is this approach correct? or is there a better option with Doctrine?)
I’m interested in learning which technique developers prefer to use to enforce uniqueness in SQL Server:UNIQUE CONSTRA开发者_运维百科INT or UNIQUE INDEX.Given that there is little difference in the p
Consider the following entity class, used with, for example, EclipseLink 2.0.2 - where the link attribute is not the开发者_JS百科 primary key, but unique nontheless.
I have the following association in my User model: has_and_belongs_to_many :friends, :class_name =>开发者_运维百科; \'User\', :foreign_key => \'friend_id\'
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