This question have been asked by several people but my problem seems to be different. Actually I have 开发者_开发问答to merge same structured tables from different databases in postgresql into a new D
I need to drop a unique constraint from a pos开发者_开发问答tgresql table, but I didn\'t give it a name in the schema. Does anybody know, how to get the name of such a constraint, or how to drop it?Th
For a table I\'m creating that include IP ranges, I need to store two 128-bit (16-byte) int values in a MySQL record.Since MySQL only supports up to 8-byte ints, I\'ve found that I need to use a binar
Original Question: Database Design: need composite key + foreign key Here\'s what I need: An auto incrementing value for Id
If a column is made unique in a database table structure, is there any need to do a check to see if a 开发者_开发问答new value to be inserted already exists in the table via script? Or would it be fin
I need to catch violation of UNIQUE constraints in a special way by a C# application I am developing. Is it safe to assume that Error 2627 will always correspond to a violation of this kind, so that I
I have little application which allows a user to rate a video. The user can rate only once. So I have defined the uniqueness on the model.
I\'m using Play\'s CRUD module to create a simple set of admin screens.One of my models is User and I want to enforce a unique constraint on the email field.
I have a data model in which a number of entities inherit some common attributes from a single superclass entity.I am using InheritanceType.JOINED on the superclass, which causes Hibernate to create a
Can one access the configuration created during an implementation of DbContext.OnModelCreating in an implementation of IDatabaseInitializer.InitializeDatabase?Given an instance of DbContext, I am unab
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