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  • [CODE GENERATION] How to generate DELETE statements in PL/SQL, based on the tables FK relations?

    - by The chicken in the kitchen
    Is it possible via script/tool to generate authomatically many delete statements based on the tables fk relations, using Oracle PL/SQL? In example: I have the table: CHICKEN (CHICKEN_CODE NUMBER) and there are 30 tables with fk references to its CHICKEN_CODE that I need to delete; there are also other 150 tables foreign-key-linked to that 30 tables that I need to delete first. Is there some tool/script PL/SQL that I can run in order to generate all the necessary delete statements based on the FK relations for me? (by the way, I know about cascade delete on the relations, but please pay attention: I CAN'T USE IT IN MY PRODUCTION DATABASE, because it's dangerous!) I'm using Oracle DataBase 10G R2. This is the result I've written, but it is not recursive: This is a view I have previously written, but of course it is not recursive! CREATE OR REPLACE FORCE VIEW RUN ( OWNER_1, CONSTRAINT_NAME_1, TABLE_NAME_1, TABLE_NAME, VINCOLO ) AS SELECT OWNER_1, CONSTRAINT_NAME_1, TABLE_NAME_1, TABLE_NAME, '(' || LTRIM ( EXTRACT (XMLAGG (XMLELEMENT ("x", ',' || COLUMN_NAME)), '/x/text()'), ',') || ')' VINCOLO FROM ( SELECT CON1.OWNER OWNER_1, CON1.TABLE_NAME TABLE_NAME_1, CON1.CONSTRAINT_NAME CONSTRAINT_NAME_1, CON1.DELETE_RULE, CON1.STATUS, CON.TABLE_NAME, CON.CONSTRAINT_NAME, COL.POSITION, COL.COLUMN_NAME FROM DBA_CONSTRAINTS CON, DBA_CONS_COLUMNS COL, DBA_CONSTRAINTS CON1 WHERE CON.OWNER = 'TABLE_OWNER' AND CON.TABLE_NAME = 'TABLE_OWNED' AND ( (CON.CONSTRAINT_TYPE = 'P') OR (CON.CONSTRAINT_TYPE = 'U')) AND COL.TABLE_NAME = CON1.TABLE_NAME AND COL.CONSTRAINT_NAME = CON1.CONSTRAINT_NAME --AND CON1.OWNER = CON.OWNER AND CON1.R_CONSTRAINT_NAME = CON.CONSTRAINT_NAME AND CON1.CONSTRAINT_TYPE = 'R' GROUP BY CON1.OWNER, CON1.TABLE_NAME, CON1.CONSTRAINT_NAME, CON1.DELETE_RULE, CON1.STATUS, CON.TABLE_NAME, CON.CONSTRAINT_NAME, COL.POSITION, COL.COLUMN_NAME) GROUP BY OWNER_1, CONSTRAINT_NAME_1, TABLE_NAME_1, TABLE_NAME; ... and it contains the error of using DBA_CONSTRAINTS instead of ALL_CONSTRAINTS...

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  • Namespace constraint with generic class decleration

    - by SomeGuy
    Good afternoon people, I would like to know if (and if so how) it is possible to define a namespace as a constraint parameter in a generic class declaration. What I have is this: namespace MyProject.Models.Entities <-- Contains my classes to be persisted in db namespace MyProject.Tests.BaseTest <-- Obvious i think Now the decleration of my 'BaseTest' class looks like so; public class BaseTest<T> This BaseTest does little more (at the time of writing) than remove all entities that were added to the database during testing. So typically I will have a test class declared as: public class MyEntityRepositoryTest : BaseTest<MyEntity> What i would LIKE to do is something similar to the following: public class BaseTest<T> where T : <is of the MyProject.Models.Entities namespace> Now i am aware that it would be entirely possible to simply declare a 'BaseEntity' class from which all entities created within the MyProject.Models.Entities namespace will inherit from; public class BaseTest<T> where T : MyBaseEntity but...I dont actually need to, or want to. Plus I am using an ORM and mapping entities with inheritance, although possible, adds a layer of complexity that is not required. So, is it possible to constrain a generic class parameter to a namespace and not a specific type ? Thank you for your time.

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  • How to do multiple column UniqueConstraint in hbm?

    - by DataSurfer
    Working on some legacy hibernate code. How do I do the following with hbm.xml(hibernate mapping file) instead of with annotations? @Table(name="users", uniqueConstraints = { @UniqueConstraint(columnNames={"username", "client"}), @UniqueConstraint(columnNames={"email", "client"}) }) public class User implements Serializable { private static final long serialVersionUID = 1L; @Id private int id; private String username; private String email; private Client client; }

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  • I'm looking for a constraint to prevent the insert of an empty string in MySQL

    - by Marga Keuvelaar
    Ok, in this question I learned how to prevent the insert of a NULL value. But, unfortunately, an empty string is being inserted anyway. Apart from preventing this on the PHP side, I'd like to use something like a database constraint to prevent this. Of course a check on the application side is necessary, but I'd like it to be on both sides. I am taught that whatever application is talking to your database, it should not be able to insert basically wrong data in it. So... CREATE TABLE IF NOT EXISTS tblFoo ( foo_id int(11) NOT NULL AUTO_INCREMENT, foo_test varchar(50) NOT NULL, PRIMARY KEY (foo_id) ); Would still allow me to do this insert: INSERT INTO tblFoo (foo_test) VALUES (''); Which I would like to prevent.

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  • XForms relation of 'constraint' and 'required' properties

    - by Danny
    As a reference, the most similar question already asked is: http://stackoverflow.com/questions/8667849/making-xforms-enforce-the-constraint-and-type-model-item-properties-only-when-fi The difference is that I cannot use the relevant properties since I do want the field to be visible and accessible. I'm attempting to make a XForms form that has the following properties: It displays a text field named 'information'. (for the example) This field must not be required, since it may not be necessary to enter data. (Or this data will be entered at a later time.) However, if data is entered in this field, it must adhere to the specified constraint. I cannot mark the field as not relevant since this would hide the field and some data may need to be entered in it. The trouble now is that even though the field has no data in it, the constraint is still enforced (i.e. even though it is not marked as 'required'). I have taken a look at the XForms 1.1 specification, however it does not seem to describe how the properties 'required' and 'constraint' should interact. The only option I see, is to add a part to the constraint such that an empty value is allowed. e.g.: . = '' or <actual-constraint However, I don't like this. It feels like a workaround to add this to every such field. Is there any other way to express that non-required fields should not need to match the constraint for that field? (Am I missing something?)

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  • MySQL Removing Some Foreign keys

    - by Drew
    I have a table whose primary key is used in several other tables and has several foreign keys to other tables. CREATE TABLE location ( locationID INT NOT NULL AUTO_INCREMENT PRIMARY KEY ... ) ENGINE = InnoDB; CREATE TABLE assignment ( assignmentID INT NOT NULL AUTO_INCREMENT PRIMARY KEY, locationID INT NOT NULL, FOREIGN KEY locationIDX (locationID) REFERENCES location (locationID) ... ) ENGINE = InnoDB; CREATE TABLE assignmentStuff ( ... assignmentID INT NOT NULL, FOREIGN KEY assignmentIDX (assignmentID) REFERENCES assignment (assignmentID) ) ENGINE = InnoDB; The problem is that when I'm trying to drop one of the foreign key columns (ie locationIDX) it gives me an "ERROR 1025 (HY000): Error on rename" error. How can I drop the column in the assignment table above without getting this error?

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  • T-SQL Unique constraint locked the SQL server

    - by PaN1C_Showt1Me
    HI ! This is my table: CREATE TABLE [ORG].[MyTable]( .. [my_column2] UNIQUEIDENTIFIER NOT NULL CONSTRAINT FK_C1 REFERENCES ORG.MyTable2 (my_column2), [my_column3] INT NOT NULL CONSTRAINT FK_C2 REFERENCES ORG.MyTable3 (my_column3) .. ) I've written this constraint to assure that combination my_column2 and my_column3 is always unique. ALTER TABLE [ORG].[MyTable] ADD CONSTRAINT UQ_MyConstraint UNIQUE NONCLUSTERED ( my_column2, my_column3 ) But then suddenly.. The DB stopped responding.. there is a lock or something.. Do you have any idea why? What is bad with the constraint?

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  • Ensure Oracle row represents a unique timespan

    - by Dan F.
    I have to make a process in Oracle/PLSQL. I have to verify that the interval of time between start_date and end_date from a new row that I create must not intersect other start_dates and end_dates from other rows. Now I need to check each row for that condition and if it doesn't correspond the repetitive instruction should stop and after that to display a message such as "The interval of time given is not correct". I don't know how to make repetitive instructions in Oracle/PLSQL and I would appreciate if you would help me.

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  • Grails' GORM constraint question

    - by xain
    Hi, I have the following Domain Class: class Metric { String name float value static belongsTo = [Person,Corporation] static indexes = { name() } } How can I add a constraint so Person,Corporation and name are unique ? Thanks.

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  • Check constraint over two columns

    - by Rippo
    I want to add a Check Constraint to a table for server 2005 but cannot work it out. MemberId ClubId MeetingId 1 100 10 2 100 10 3 100 10 7 101 10 <-This would throw a check constraint 1 100 11 2 100 11 I do not want to have more than one ClubId for a single MeetingId Basically a ClubId can only belong to a single MeetingId but can have more than one member assigned. How do I achieve this?

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  • how can i set up a uniqueness constraint in mysql for columns that can be null?

    - by user299689
    I know that in MySQL, UNIQUE constraits don't treat NULL values as equal. So if I have a unique constraint on ColumnX, then two separate rows can have values of NULL for ColumnX and this wouldn't violate the constraint. How can I work around this? I can't just set the value to an arbitrary constant that I can flag, because ColumnX in my case is actually a foreign key to another table. What are my options here? Please note that this table also has an "id" column that is its primary key. Since I'm using Ruby on Rails, it's important to keep this id column as the primary key. Note 2: In reality, my unique key encompasses many columns, and some of them have to be null, because they are foreign keys, and only one of them should be non-null. What I'm actually trying to do is to "simulate" a polymorphic relationship in a way that keep referential integrity in the db, but using the technique outlined in the first part of the question asked here: http://stackoverflow.com/questions/922184/why-can-you-not-have-a-foreign-key-in-a-polymorphic-association

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  • Do I need to write a trigger for such a simple constraint?

    - by Paul Hanbury
    I really had a hard time knowing what words to put into the title of my question, as I am not especially sure if there is a database pattern related to my problem. I will try to simplify matters as much as possible to get directly to the heart of the issue. Suppose I have some tables. The first one is a list of widget types: create table widget_types ( widget_type_id number(7,0) primary key, description varchar2(50) ); The next one contains icons: create table icons ( icon_id number(7,0) primary key, picture blob ); Even though the users get to select their preferred widget, there is a predefined subset of widgets that they can choose from for each widget type. create table icon_associations ( widget_type_id number(7,0) references widget_types, icon_id number(7,0) references icons, primary key (widget_type_id, icon_id) ); create table icon_prefs ( user_id number(7,0) references users, widget_type_id number(7,0), icon_id number(7,0), primary key (user_id, widget_type_id), foreign key (widget_type_id, icon_id) references icon_associations ); Pretty simple so far. Let us now assume that if we are displaying an icon to a user who has not set up his preferences, we choose one of the appropriate images associated with the current widget. I'd like to specify the preferred icon to display in such a case, and here's where I run into my problem: alter table icon_associations add ( is_preferred char(1) check( is_preferred in ('y','n') ) ) ; I do not see how I can enforce that for each widget_type there is one, and only one, row having is_preferred set to 'y'. I know that in MySQL, I am able to write a subquery in my check constraint to quickly resolve this issue. This is not possible with Oracle. Is my mistake that this column has no business being in the icon_associations table? If not where should it go? Is this a case where, in Oracle, the constraint can only be handled with a trigger? I ask only because I'd like to go the constraint route if at all possible. Thanks so much for your help, Paul

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  • Check if a type is an instantiation of a template

    - by Pedro Lacerda
    I have structs like struct RGBA (T) {/* ... */} struct BMPFile (DataT) if (is(DataT == RGBA)) {/* ... */} But is(DataT == RGBA) cannot work because DataT is a type and RGBA is a template. Instead I need check if a type is an instantiation of a template in order to declare file like BMPFile!(RGBA!ushort) file; In a comment @FeepingCreature showed struct RGBA(T) { alias void isRGBAStruct; } struct BMPFile (DataT) if (is(DataT.isRGBAStruct)) {} Although to be working I have no tips on alias void isRGBAStruct.

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  • How do I make a GUI that behaves like this?

    - by Karl Knechtel
    This is difficult to explain without illustration, so - behold, an illustration, cobbled together from screenshots of a few hello-world examples and a lot of Paint work: I have started out using Windows Forms on .NET (via IronPython, but that shouldn't be important), and haven't been able to figure out very much. GUI libraries in general are very intimidating, simply because every class has so many possible attributes. Documentation is good at explaining what everything does, but not so good at helping you figure out what you need. I will be assembling the GUI dynamically, but I'm not expecting that to be the hard part. The sticking points for me right now are: How do I get text labels to size themselves automatically to the width of the contained text (so that the text doesn't clip, and I also don't reserve unnecessary space for them when resizing the window)? How do I make the vertical scrollbar always appear? Setting the VScroll property (why is this protected when AutoScroll is public, BTW?) doesn't seem to do anything. How come the horizontal scrollbar is not added by AutoScroll when contents are laid out vertically (via Dock = DockStyle.Top)? I can use a minimum size for panels to prevent the label and corresponding control from overlapping when the window is shrunk horizontally, but then the scrollbar doesn't appear and the control is inaccessible. How can I put limits on window resizing (e.g. set a minimum width) without disabling it completely? (Just set minimum/maximum sizes for the Form?) Related to that, is there any way to set minimum/maximum widths or heights without setting a minimum/maximum size (i.e. can I constrain the size in only one dimension)? Is there a built-in control suitable for hex editing or am I going to have to build something myself? ... And should I be using something else (perhaps something more capable?) I've heard WPF mentioned, but I understand that this involves XML and I really want to build a GUI from XML - I already have data in an object graph, and doing some kind of weird XML pseudo-serialization (in Python, no less!) in order to create a GUI seems incredibly roundabout.

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  • Symfony 1.4: Deleting a sfGuardUser

    - by Tom
    Hi, I'm having some trouble with the following... I have a sfGuardUser table set up normally, and it has a one-to-one relationship with a Profile table, which contains some additional user info. When a user wants to delete themselves from the site, I'd like to retain their info in the Profile table for various purposes BUT delete the sfGuardUser in order to keep that table cleaner/shorter (not just set it to inactive). I was under the impression that I could set the FK in the Profile table to NULL and then delete the sfGuardUser, but it seems the FK-constraint fails. Indeed, it seems I can't delete either and the queries fail: If I try to delete the sfGuardUser, the Profile table will have an invalid FK If I try to delete a Profile, the sfGuardUser will have an invalid FK Other than leaving outdated sfGuardUsers and Profiles in these tables, or having to use a cascaded delete to get rid of both, can anyone tell me if there's any other way around this? Thank you.

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  • Unable to drop constraint in sql server 2005 "Could not drop constraint. See previous errors"

    - by DannykPowell
    I'm trying to drop a constraint on a db table, something like: ALTER TABLE MyTable drop CONSTRAINT FK_MyTable_AnotherTable But the execution just runs and runs. If I stop it I see: Msg 3727, Level 16, State 0, Line 2 Could not drop constraint. See previous errors. Web search throws up various pages but note that the constraint is properly named and I am trying to remove it using the correct name

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  • How to find the entity with the greatest primary key?

    - by simpatico
    I've an entity LearningUnit that has an int primary key. Actually, it has nothing more. Entity Concept has the following relationship with it: @ManyToOne @Size(min=1,max=7) private LearningUnit learningUnit; In a constructor of Concept I need to retrieve the LearningUnit with the greatest primary key. If no LearningUnit exists yet I instantiate one. I then set this.learningUnit to the retrieved/instantied. Finally, I call the empty constructor of Concept in a try-catch block, to have the entitymanager do the cardinality check. If an exception is thrown (I expect one in the case that already another 7 Concepts are referring to the same LearningUnit. In that case, I case instantiate a new LearningUnit with a new greater primary key. Please, also point out, if any, clear pitfalls in my outlined algorithm above.

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  • How should I do this (business logic) in Sql Server? A constraint?

    - by Pure.Krome
    Hi folks, I wish to add some type of business logic constraint to a table, but not sure how / where. I have a table with the following fields. ID INTEGER IDENTITY HubId INTEGER CategoryId INTEGER IsFeatured BIT Foo NVARCHAR(200) etc. So what i wish is that you can only have one featured thingy, per articleId + hubId. eg. 1, 1, 1, 1, 'blah' -- Ok. 2, 1, 2, 1, 'more blah' -- Also Ok 3, 1, 1, 1, 'aaa' -- constraint error 4, 1, 1, 0, 'asdasdad' -- Ok. 5, 1, 1, 0, 'bbbb' -- Ok. etc. so the third row to be inserterd would fail because that hub AND category already have a featured thingy. Is this possible?

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  • Why can I create a table with PRIMARY KEY on a nullable column?

    - by AlexKuznetsov
    The following code creates a table without raising any errors: CREATE TABLE test( ID INTEGER NULL, CONSTRAINT PK_test PRIMARY KEY(ID) ) Note that I cannot insert a NULL, as expected: INSERT INTO test VALUES(1),(NULL) ERROR: null value in column "id" violates not-null constraint DETAIL: Failing row contains (null). ********** Error ********** ERROR: null value in column "id" violates not-null constraint SQL state: 23502 Detail: Failing row contains (null). Why can I create a table with a self-contradictory definition? ID column is explicitly declared as NULLable, and it is implicitly not nullable, as a part of the PRIMARY KEY. Does it make sense? Edit: would it not be better if this self-contradictory CREATE TABLE just failed right there?

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  • C# overloading with generics: bug or feature?

    - by TN
    Let's have a following simplified example: void Foo<T>(IEnumerable<T> collection, params T[] items) { // ... } void Foo<C, T>(C collection, T item) where C : ICollection<T> { // ... } void Main() { Foo((IEnumerable<int>)new[] { 1 }, 2); } Compiler says: The type 'System.Collections.Generic.IEnumerable' cannot be used as type parameter 'C' in the generic type or method 'UserQuery.Foo(C, T)'. There is no implicit reference conversion from 'System.Collections.Generic.IEnumerable' to 'System.Collections.Generic.ICollection'. If I change Main to: void Main() { Foo<int>((IEnumerable<int>)new[] { 1 }, 2); } It will work ok. Why compiler does not choose the right overload?

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  • C++ enforce conditions on inherited classes

    - by user231536
    I would like to define an abstract base class X and enforce the following: a) every concrete class Y that inherits from X define a constructor Y(int x) b) it should be possible to test whether two Y objects are equal. For a, one not very good solution is to put a pure virtual fromInt method in X which concrete class will have to define. But I cannot enforce construction. For b), I cannot seem to use a pure virtual method in X bool operator == (const X& other) const =0; because in overridden classes this remains undefined. It is not enough to define bool operator == (const Y& other) const { //stuff} because the types don't match. How do I solve these problems?

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  • What happened to my "Predefined rules" in Windows Firewall? How can I get them back?

    - by Cheeso
    Windows Firewall Advanced Settings in Windows 7 , has predefined rule sets. When I click the "Add Rule..." button in my Windows 7 Ultimate install, it looks like this: But, on a machine I have that runs Windows 7 Home Premium, when I click "Add Rule...", the "predefined rules" option is greyed out. Like this: Is this expected? Does Win7 Home Premium NOT have predefined rules? How can I get the rules back?

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