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Referential integrity for mysql
You only have to index the fields used in the foreign key relationships, and recent version of mysql do this automatically for you anyways. It's not "overkill". it's actually an optimization. Consider that anytime you update/delete/insert a record, the foreign tables have to be checked for matching records - without the indexes, those checks could be glacially slow.

Categories : PHP

How can I perform exception handling in MySQL (referential integrity)
You can not set CustomerId = null because of you have customerid column in address table is FOREIGN key and customer table, customerid column is a primary key and primary key don't have null value. UPDATE `Address` R SET R.CustomerId = NULL

Categories : Mysql

Merge two large MySQL databases whilst maintaining referential integrity
I think a good idea is make a script to migrate data and then iterate over the small database and add the records to the bigger database. Make tests in a development environment and after confirm that it works, run in production.

Categories : Mysql

Referential integrity access
Your intersection table should not include the Program/Partner Names at all, it should only include the Program/Partner ID values. By keeping a copy of the names in the intersection table you have denormalized your data. This is generally considered to be a "Bad Thing".

Categories : Database

How to implement referential integrity here?
I think you can just use foreign keys as you would expect: CREATE TABLE [dbo].[Documents]( [DocID] [int] IDENTITY(1,1) NOT NULL, [NoDoc] [char](9) NULL, [IdClient] [varchar](10) NULL, [AdrNum] [tinyint] NULL, [DateDoc] [smalldatetime] NOT NULL, CONSTRAINT [PK_DocID] PRIMARY KEY (DocId), CONSTRAINT FK_DOC_Clients FOREIGN KEY (IdClient) references Clients (IdClient), CONSTRAINT FK_Doc_Addresses FOREIGN KEY (IdClient,AdrNum) references DeliveryAddresses (IdClient,AdrNum) ) If one or more column values in the referencing side of a foreign key is NULL, then the foreign key constraint is not checked. Conversely, there's no way to have NULL be a foreign key reference.

Categories : Sql Server

Does SQLite support referential integrity?
SQLite does not enforce foreign key constraints by default (mostly to be backward compatible). To enable it, you have to execute PRAGMA foreign_keys = 1 after you connected to the database. See the manual about PRAGMA foreign_keys for more details.

Categories : Django

Referential integrity checking in table definition
Have you tried using the SQL CHECK constraint? http://www.w3schools.com/sql/sql_check.asp You're going to need a composite foreign key to provide the check you want.

Categories : SQL

Removing Referential Integrity on Stable Application
It will vary from application to application. So "how much" will be a relative term. Performance benefit will come while inserting or deleting records. So if you have big insertion or deletion operations which are taking time then it might help but i will not suggest you to drop it even if your application is stable because in future development this might lead to big issues.

Categories : SQL

Referential integrity for invoice and task tables
So far I have come up with a task_id1, task_id2, etc... fields on the invoices table that are foreign keys to the task_id field Alternatively the invoices table could have a comma separated list of task_id's that would allow for a variable amount of tasks per invoice NOO!!! Make a many-to-many tables between invoices and tasks, and make the constraint between this table and both the invoice and task table. SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0; SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0; SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='TRADITIONAL,ALLOW_INVALID_DATES'; CREATE SCHEMA IF NOT EXISTS `mydb` DEFAULT CHARACTER SET latin1 COLLATE latin1_swedish_ci ; USE `mydb` ; -- ----------------------------------------------------- -- Tabl

Categories : Mysql

How to enforce referential constraints (foreign keys)
Try to add "engine=InnoDB" when you create the tables. Depending on version and platform, the default storage format for tables is MyISAM, and there referential integrity is not checked. Here is an example from 5.0.91-log MySQL Community Server running on Linux: mysql> CREATE TABLE Department -> (dno INTEGER NOT NULL, -> PRIMARY KEY (dno)); Query OK, 0 rows affected (0.04 sec) mysql> CREATE TABLE Employee -> (eno INTEGER NOT NULL, -> works_at INTEGER NOT NULL, -> PRIMARY KEY (eno), -> FOREIGN KEY (works_at) REFERENCES Department(dno)); Query OK, 0 rows affected (0.03 sec) mysql> INSERT INTO Employee (eno, works_at) VALUES (17, 4711); Query OK, 1 row affected (0.02 sec) mysql> DROP TABLE Employee; Query OK, 0 rows affected (0.00 se

Categories : Mysql

Enforcing referential integrity on among distantly related tables
Yes, there is a way. You can add unique constraint to table TableC: CREATE TABLE [TableC] ( [ID] INT NOT NULL IDENTITY (1, 1) PRIMARY KEY , [A_ID] INT NOT NULL FOREIGN KEY REFERENCES [TableA] ([ID]), CONSTRAINT UK_TableC UNIQUE ([ID], [A_ID]) ) and then you will be able referencing TableC in table TableD as you specified: CREATE TABLE [TableD] ( [ID] INT NOT NULL IDENTITY (1, 1) PRIMARY KEY , [C_ID] INT NOT NULL , [A_ID] INT NOT NULL , [Value] TINYINT NOT NULL , FOREIGN KEY ([C_ID], [A_ID]) REFERENCES [TableC] ([ID], [A_ID]) , FOREIGN KEY ([A_ID], [Value]) REFERENCES [TableB] ([A_ID], [Value]) )

Categories : SQL

Fixtures Plugin Referential Integrity Exceptions In Grails
Your simplified version of code (except hasMany in Bar) works for me without any FK exception. Although I would prefer a different approach to achieve a true one-one bidirectional relationship if I am correct with the parent and child mapping. Below is my setup which works fine without the FK constraint exception. Note that I have also mentioned in comments how would I achieve true one-to-one bidirectional assuming Foo has one Bar and has one Baz. class Foo implements Serializable{ String someValue1 String someValue2 String whatever //True one to one can be achieved by doing as below //static hasOne = [bar: Bar, baz: Baz] Bar bar Baz baz static mapping = { id composite: ['someValue1', 'someValue2'], generator: 'assigned' columns {

Categories : Grails

Referential Integrity error with dimension processing for cube
Are you sure that the dimension is processed? Remember that as it links the facts to the dimensions, it does so on the SSAS dimension, not the underlying SQL table. Try running a process(Update) on the dimension first? In your original post you're mixing upper and lower case, MARKETPLACE and Marketplace. Is this how it is in the source? It could be that it isn't treating them as the same. I've seen SSAS have issues with "Id" versus "ID" Possible relative of ssas attribute key cannot be found even though it exists and is not due to duplicates Edited comments into answer after acceptance.

Categories : SQL

Error:A referential integrity constraint violation occurred on db.SaveChanges() in .net?
You instantiate phnumber only once and then try to insert it in the database multiple times. Move the PhoneNumber phnumber = new PhoneNumber(); phrase inside the foreach (var ph in phoneList) Block.

Categories : Dotnet

Referential integrity constraint violation on owner delete (OneToMany unidirectional)
When you delete an Acronym, it's associated Expansion objects get deleted. However, on the Tag table, there's a foreign key to the Expansion table, which prevents the Expansion from being deleted. I suggest that you revisit your design and think carefully about the delete functionality and whether you really want the deletion of the Acronym to delete all the related Expansions and Tags. This doesn't seem like a realistic usecase.

Categories : Java

Integrity constraint in MySQL to express "must have one primary attribute"
Does it work any better if you swap ... ALTER TABLE MEMBERS ADD CONSTRAINT oneprimary_ck CHECK (SELECT COUNT(isprimary)=1 FROM TELEPHONENUMBERS WHERE TELEPHONENUMBERS.membershipnumber = membershipnumber) IN '1'; ... with ... ALTER TABLE MEMBERS ADD CONSTRAINT oneprimary_ck CHECK (SELECT COUNT(isprimary) FROM TELEPHONENUMBERS WHERE isprimary=1 AND TELEPHONENUMBERS.membershipnumber = membershipnumber) > 1; ... ?

Categories : Mysql

How to enforce foreign key constraint from unrelated tables in Mysql?
Side note :I believe you gave too many details in your question, so I apologize if I misunderstood it. Taking into account you use mysql which doesn't have materialized views that could be used to enforce desired constraint, I see two options. First, you can mimic materialized view with trigger[s] and a new table with unique constraint (it will work, but it's quite hard to implement in general - you have to make sure all INSERT/UPDATE/DELETE on 3 tables are handled properly by corresponding triggers). Another way is to denormalize your schema by adding groupId to Ledger , and "extra" unique constraint on Users (userId, groupId) and Accounts (acid,groupId), and changing FKs in Ledger so it refers not to userId in Users, but to userId,groupId and not to acid, but to acid,groupId. I hope

Categories : Mysql

In MySQL, Is there a programmatically way to check data's integrity before altering encoding/collation of a column?
The canonical way for this is to try it out: Use SHOW CREATE TABLE to create an identically-structured testing table Use INSERT INTO .. SELECT .. to populate the testing table with the primary key and relevant column(s) of the original Try out conversion, noting necessary steps to fix problems Rinse and repeat

Categories : Mysql

MySQL - This version of MySQL doesn't yet support 'LIMIT & IN/ALL/ANY/SOME subquery
you dont need a subquery here .try this SELECT VID, thumb FROM video WHERE title LIKE "%'.$Channel['name'].'%" ORDER BY RAND() DESC LIMIT 1 In MySQL 5.0.26 and later MySQL does not support LIMIT in subqueries for certain subquery operators: link

Categories : PHP

php doesn't execute the query of mysql, but in mysql it's executable
Perhaps this should help: $strQry = "INSERT INTO resource (id_mission, name, ressource_path, assignment, position) SELECT ".$new_id_mis.", name, ressource_path, assignment, position FROM resource WHERE id_mission=".$id_mission; mysql_query($strQry);

Categories : PHP

getting parent in self referential model
You need to modify the association parent_category. There you have to specify the foreign key. belongs_to :parent_category, class_name: "Category", foreign_key: 'parent_id'

Categories : Ruby On Rails

Self Referential Relationship in SQLAlchemy
What you are doing is not a self-referential many-to-many, it is a self-referential one-to-many (one parent has many children). First of all, you do not need to have the is_parent boolean. You can easily determine if an issue is a parent by looking at the parent_id field, which would point to itself only for parents. You could add the following helper method to your Issue class: def is_parent(self): return self.parent_id == self.id To obtain the siblings of an issue you can write a custom query that gets all the issues that have the same parent_id except the one the query is issued on: def get_siblings(self): return Issue.query.filter(Issue.parent_id == self.parent_id, Issue.id != self.id).all()

Categories : Python

How to Model self-referential Entities in SQL
Yes, that would be it, but you can simplify: Table Element idElement | name Table Weakness idRow | idElement |idElementStrongAgainst No need to add a strength table, you just have to look at the weakness table entering by the other column. So to find the strengths of water you do SELECT strVS.Name FROM Element AS el JOIN Weakness on el.idElement = Weakness.idElement JOIN Element As strVS on weakness.idElementStrongAgainst= strVS.idElement WHERE el.Name = 'water' and to find the weaknesses: SELECT weakVS.Name FROM Element AS el JOIN Weakness on el.idElement = Weakness.idElementStrongAgainst JOIN Element As weakVS on weakness.idElement = weakVS.idElement WHERE el.Name = 'water'

Categories : SQL

referential actions with trigger
Given that the least objectionable of the options you listed is to do a cascading delete when a parent row is removed CREATE OR REPLACE TRIGGER trigger_name AFTER DELETE ON parent_table FOR EACH ROW BEGIN DELETE FROM child_table WHERE parent_id = :old.parent_id; <<repeat for each child table>> END;

Categories : Oracle

Using self-referential arrays, polygons are invisible
You initialize the values in your arrays like this: xC[0]= (int)Math.random()*400; But the cast happens before the multiplication, so the value returned by Math.random() (which will be less than 1) gets cast to an int, so it becomes 0*400, therefore 0 gets stored into all the indices of your array. To fix this, just put parentheses around the multiplication so it looks like: xC[0]= (int)(Math.random()*400); I should also note that your loop is just drawing the same triangle 14 times, so you still won't see a bunch of different triangles. To fix that, just put the code you use to generate your triangles inside of your loop, like so: for (int i = 0; i < 14; i++) { int[] xC = new int[3]; xC[0] = (int) (Math.random() * 400); xC[1] = xC[0] + (int) (Math.random() * 200);

Categories : Java

Find parent with no children in self-referential relationship
I don't know of a more rubyish method , but the SQL method would be more efficient where multiple children might exist as: scope :without_children, where("not exists (select null from children where children.parent_id = tasks.id)") People seem to love that outer join method, possibly because of an inefficient implementation of the not exists method in some databases, but with not exists a half-decent query optimiser will use a semi-join that stops looking for other children after finding the first.

Categories : Ruby On Rails

ruby on rails form_for self referential model
I was able to figure out how to move the logic out of the form. Basically the object being passed to the form_for helper needs to be initialized. I put the initialization logic into user helper and passed the method to the form_for helper. so this is what you get user helper method def initializing_relationships current_user.relationships.build(followed_id: @user.id) end in the form you call initializing_relationships <%= form_for(initializing_relationships) do |f| %> This really cleans up the form.

Categories : Ruby On Rails

Why become referential constraints inconsistent after updating foreign key?
Figured out the problem: apparently it makes quite the difference when to set navigational properties to null, as EF might otherwise interpret that as an intended change / update (at least that is what I suspect). The following version of the MarkAs method works: private void MarkAs(User user, UserAddress address, User.AddressType type) { if (context.Entry(user).State == EntityState.Detached) { // clear navigation properties before attaching the entity user.DefaultInvoiceAddress = null; user.DefaultDeliveryAddress = null; context.Users.Attach(user); } // address doesn't have to be attached if (type.HasFlag(User.AddressType.DefaultInvoice)) { // previously I tried to clear the navigation property

Categories : C#

EF Power Tools confused by Self Referential Table
I couldn't find some of the classes in that post. I did get this working using another article. The Item class ended up as: public partial class Item ... public virtual int? ParentId { get; set; } public virtual Item Parent { get; set; } public virtual ICollection<Item> Children { get; set; } } The mapping class needed: this.HasOptional(x => x.Parent) .WithMany(x => x.Children) .HasForeignKey(x => x.ParentId) .WillCascadeOnDelete(false); It seemed to work. I didn't need any of the ProxyCreation or CreateObject commands... The big problem is that I can't use the EF power tools anymore to generate any new Poco classes.

Categories : C#

Rails self-referential nested association not working with scope
I think you got the word 'house' because that is what you asked for, a word that has the entry 'house'. I would take a two staged approach, kind of like you did with your "what works" example. class Word < ActiveRecord::Base has_and_belongs_to_many :meanings has_many :synonyms, :through => :meanings end Word.where(entry: 'house').first.synonyms This assumes that the word exists... In practice you would check for the existence of the word before calling for its synonyms.

Categories : Ruby On Rails

User-oriented sparql on views and referential graphs
I've never tried to do something like this with the API but it should be possible. I would probably recommend not using SparqlView implementations unless the criteria for what data can be seen by each user is only expressible as a SPARQL query, a SparqlView is fairly expensive in memory terms since it takes a copy of the original data and is not currently a direct view over the underlying data (theoretically this is possible but would require a lot more coding and would trade off lower memory usage for performance). From what you have described I would suggest the best approach might be to use a custom ISparqlDataset implementation, likely deriving from the decorator WrapperDataset. This way you can intercept all the calls that SPARQL queries will make and restrict exactly what each ins

Categories : Misc

breezejs: adding referential constraint to an entity type
So you are getting meta data but it doesn't have a relationship between the entities. Hmm I have not gotten metaData AND tried to create additional model properties that are related. Your best bet is to add a property that is a navigation type on the constructor. http://www.breezejs.com/sites/all/apidocs/classes/EntityType.html#method_addProperty If it were me, I would try it this way (or something similar) inside of the constructor - myEntity.addProperty({ associatedEntity: { entityTypeName: "AssociatedEntity", isScalar: true, associationName: "AssociatedEntity_MyEntitys", foreignKeyNames: ["associatedEntityId"] } }); Where myEntity is the name of the current entity, AssociatedEntity would be y

Categories : Javascript

Fixing Memory Leaks in Chapter 6.5 Example in the K&R book (Self-Referential Structures)
To fix that, create a recursive function who looks like your print function to free you tree. An example : void free_tree (struct tnode *p) { if(p != NULL) { free_tree(p->left); free_tree(p->right); free( p->word ); free( p ); } } You can put it in the main after treeprint : int main(void) { ... treeprint(root); free_tree( root ); // ^^^^^^^^^^^^^^^ return 0; }

Categories : C

e:Core data self referential relationships lost after application relaunch
You need to delete application from the Simulator or the Device. Because using the same reference from the persistent co-ordinate will cause a problem in the relationship. Deleting app before relaunching will solve the problem.

Categories : IOS

Infinite type error when returning a self-referential function in haskell
To express something like this, you'd need a recursive type. Since Haskell doesn't support equirecursive types, you'll need to use newtype/data. So you might define newtype Foo s = Foo { runFoo :: s -> (s, Foo s) }, for instance, and then write noOp :: Foo (A,B,C); noOp = Foo ((a,b,c) -> ((a,b,c), noOp)). This looks like a Mealy machine. The package machines exports a similar type: newtype Mealy i o = Mealy { runMealy :: i -> (o, Mealy i o) }

Categories : Haskell

API Integrity issue?
Subtasks are first-class tasks and can belong to projects in their own right. So, for example, if task A has subtask B, and subtask B is in project P, then when you fetch tasks for project P, you will get B in the results. Does this map to what you're seeing, or is the subtask not explicitly in the project you requested?

Categories : Api

sqlalchemy integrity error
Indeed your method is prone to integrity errors. What happens is that when you invoke Foo.get(1,2,3) 2 times, you do not flush the session in between. The second time you invoke it, the ORM query fails again - because there is no actual row in the DB yet - and a new object is created, with different identity. Then on commit/flush these 2 clash causing the integrity error. This can be avoided by flushing the DB after each object creation. Now, things work differently in SQLAlchemy if the primary key is known in merge/ORM get - if the matching primary key is found already loaded in the session, SQLAlchemy realizes that these 2 must be the same object. However no such checks are done on unique indexes. It might be possible to do that also. However it would make race conditions only rarer, as

Categories : Python

PDO Integrity constraint violation
Seeing how there's an error even though you have a ON DUPLICATE KEY construct, it would be likely the problem is in the UPDATE portion. I noticed that you're reusing :nid twice; you will want to use a different alias for the second occurrence, i.e.: INSERT INTO totalresponses (nid, created) VALUES(:nid, :created) ON DUPLICATE KEY UPDATE nid = :nid2, created = :created '); Then bind :nid2 to $item['nid']. From the PDO::prepare() manual entry: You cannot use a named parameter marker of the same name twice in a prepared statement.

Categories : PHP

Use Cityhash for file integrity
This is not an appropriate application for CityHash, and it will exhibit poor collision resistance when used this way. If you want a quick file integrity checksum, use a CRC family function, like CRC16. If you want something more extensive, the speed of cryptographic hashes such as SHA1 should be more than sufficient. (Almost any modern CPU can hash data basically as fast as it can read it from memory.)

Categories : C++

How to ensure the integrity of application data?
I know that Android supports MODE_PRIVATE flag when creating a file so that no other application can access it This is the default behavior for internal storage. however is there a way to like add a digital signature or something that the application can check on startup? You are welcome to create a digital signature for a file. Anyone who modifies the file is welcome to modify the digital signature. will that prevent the user from accessing/deleting the file(s) from file manager or any other app? Ordinary users will not be able to access files on internal storage. Users who root their device are able to access internal storage if they choose to. If not, could you suggest a method to add a digital signature to the file(s) in the onDestroy() method of the MainActivity a

Categories : Java



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