I've created APTax dac class, added view for it in graph:
public PXSelect<APTax> taxes;
then in my graph I have the following:
var currentTax = taxes.Cache.Current;
currentTax.Percent = 3.25;
//some other assignments
taxes.Cache.Update(currentTax);
taxes.Cache.Persist(PXDBOperation.Update);
but I receive error message APTax was modified by another process. What I've missed?
I propose you to check how you located in your class attribute IsKey. Most often I got this error message in cases when in db I had one configuration of keys fields, but in DAC class another. They not necessary should be the same, but IsKey should be located in your DAC class uniquely.
Related
I'm trying to learn Grails but am still pretty much on beginner level.
I made a tiny application, where you can basically add events, and people can write reviews about them and rate them.
So I have an eventController and reviewController. The rating is just an Integer in a review. But now I want to show an overall rating for an event. So the events rating should be the average value of the corresponding ratings value.
This is my event domain code where the rating is initially set, I left out the constraints and toString:
class Event {
Double dRating = 2
static hasMany = [ratings:Rating]
}
The controller is simply:
class EventController {
def scaffold = Event
}
The rating domain file:
class Rating {
String comment
java.util.Date date = new java.util.Date()
Integer rating
Event event
}
and the Rating Controller is:
class RatingController {
def scaffold = Rating
}
Hope I didn't make mistakes, I had to translate variable names so they're understandable.
I'm guessing that where dRating is set, I could somehow add some calculation, but I don't even know how to access the values of the rating, and everything I try ends in lots of errors and having to restart the app again and again. I tried adding calculations in the controller, but there I don't know how to get the value into the database. So where do I actually put the logic, and how do I access the values?
If any other file is important, please tell me.
Hoping to get some hints on how to start doing this, I didn't think it would be this hard.
At first I would recommend start reading grails doc. Later from your question it is not much clear what you are asking a there could be several places or possibilities of setting up the value in domain field and persist it to database. I'm telling all of these which are known to me:
If it is generalised calculation that needs to be applied to your dRating field, then create a setter with standard bean naming convention and do this there. For example, you want to find percentage from say 1000 and then add it to dRating
class Event {
static hasMany = [ratings:Rating]
Double dRating
void setDRating(Double value){
this.dRating = value * 100/1000 // alternatively value /10
}
}
Do it in commandObject: If you don't want to put certain calculations and validation in domain then put these in command objects. See this. You can at any point of time assign values from command object to domain object by .properties binding mechanism. For example,
yourDomainObject.properties = yourcommandObjectObject.properties
Remember properties having same name would be binded.
Do it in service: You can do your calculations in service method, inject that service into your controller and call that method to perform calculations and even to persist to db as well. Remember services are by default transactional.
Hope it helps!
For a project I'm currently working on I need to dynamically add properties to a domain class and persist them later in the database. In general, I need a key/value store attached to a "normal" domain class. Sadly I cannot use a NoSQL database (e.g. Redis).
My approach would be to handle the additional properties on a save() by identifying them within afterInsert or afterUpdate and writing them to another table - I would prefer not to use a map property within the domain class but an additional "Field" table (to better support searches).
I tried to add properties using the metaClass approach:
person.metaClass.middlename = "Biterius"
assert person.middlename == "Biterius" // OK
This works and I can identify the additional properties in the afterInsert/afterUpdate methods but it seems that I cannot change the value thereafter - i.e., the following does not work:
person.middlename = "Tiberius"
assert person.middlename == "Tiberius" // FAIL
Then I tried an Expando approach by extending the Person class by the Expando class (directly ("Person extends Expando") and via an abstract intermediate class ("Person extends AbstractPerson" and "AbstractPerson extends Expando")).
def person = new Person()
assert person in Person // OK
assert person in AbstractPerson // OK
assert person in Expando // OK
Both variants did not work - I could assign values to arbitrary "properties" but the values were not stored!
person.mynewproperty = "Tiberius" // no MissingPropertyException is thrown
println person.mynewproperty // returns null
So how can I add properties to a domain class programmatically during runtime, change them and retrieve them during afterInsert or afterUpdate in order to "manually" store them in a "Fields" table?
Or am I doing something completely wrong? Are there other / simpler ways to do this?
What about turning your DB into a "NoSQL" one?
In one of my projects, I just used a String-property to store a map as JSON-Object.
For Groovy it's not a big problem to convert between a map and a JSON-Object. And since you can access a map just like an object with properties, I found this solution very convenient.
Only drawback: you have to plan the size of your String-property in advance...
Update: sorry, just read that you want to support searches...
what about
class Person {
...
static hasMany = [extProperties:KeyValue]
...
def invokeMethod(String name, args) {
if (name.startsWith('get')) {
//an unknown properties's getter is called
}
//add same for setter
}
}
class KeyValue {
String key
String value
}
I guess such a schema would give you all freedom you need. Even without the hasMany, you can make use of invokeMethod to handle your external tables...
The getter and setter can save your values in a transient string propertie (static transients = ['myTransientProperty']). This property should be available in the afterInsert / `afterUpdate´ events.
Why don't you just create a map of strings on the domain object and store your extra data there manually? Unless you're storing complex data you should be able to cast anything you need to/from a string.
I want to let the user to create multiple instances of the same form (let's call it Form1 which is a MDI child form). So I have two procedures like this where I create the forms.
procedure MyProcedure1; // procedure 2 is similar. it also has a var called MyFrm
var MyFrm: TFrm1;
begin
...
MyFrm:= TFrm1.create(MainForm);
MyFrm.BringToFront;
MyFrm.LoadFromFile(someFile);
end;
As you can see MyFrm is local var. This is ok for me as I don't need to programatically access the form after I create it. There is no other global variable named Frm1. In the OnClose event of MyFrm I have Action:= caFree;
What could cause the error above?
A user sent that error. It happened only once and I cannot reproduce it.
Edit:
The error appears in the "MyFrm:= TFrm1.create" line.
Some people suggested that I need to programatically give unique names to my dynamically created forms. I also wondered myself what name a form takes when it is created so I stepped into the code while calling the MyProcedure1 procedure.
Delphi automatically gives unique names like
MyFrm.name= MyFrm, then
MyFrm.name= MyFrm_1,
MyFrm.name= MyFrm_2,
MyFrm.name= MyFrm_3, and so on.
The MyFrm.Name is not altered in LoadFromFile. I have checked (breakpoint) the value of 'MyFrm.Name' at the end of procedure MyProcedure1; after LoadFromFile. The name is unique.
As some people suggested, I override the SetName procedure and checked the name of TMyFrm. Indeed each form gets a unique name.
procedure TMyFrm.SetName(const Value: TComponentName);
begin
ShowMessage(Value);
inherited;
end;
I have many forms in this app but only the MainForm is auto-created.
I don't use threads. Anyway this will not be relevant since the forms are created by user (so multi-threading is irrelevant unless the user can create 2 forms at the same time).
Giving MainForm as the Owner in TFrm1.Create will include the newly created form in the components list of MainForm. A component ensures that this list doesn't contain any two components with the same non-empty name (otherwise FindComponent won't work). This mechanism also works when a component changes its name.
As long as you don't specify the name in TFrm1.Create it is most likely that it is set by the LoadFromFile method, which means that you don't have much influence on the name unless you change the file's content.
A valid workaround is to create the form with nil as Owner, load the form from the file, change the name to a unique value or to an empty string and finally call MainForm.InsertComponent.
procedure MyProcedure1;
var MyFrm: TFrm1;
begin
...
MyFrm:= TFrm1.create(nil);
MyFrm.BringToFront;
MyFrm.LoadFromFile(someFile);
MyFrm.Name := ''; // or some unique name
MainForm.InsertComponent(MyFrm);
end;
The message is caused because each form must be uniquely named.
When you create a form twice, you need to ensure each instance has a unique name, or set the Name to an empty string. The latter also is the trick when using multiple instances of a data module, so that the automatic linking of data-aware controls does not end up always using the first instance.
Add
MyFrm.Name := MyFrm.Name + <something unique>;
MyFrm.Name := '';
after the Create call and you should be fine
MyFrm.Name is the same for both instances...
Make sure than MyFrm.Name is unique...
As far as my exploration along this line, yes the problem of "already exists" stems from having intances of the editor with the same value for the Name property. As another work around do not visually create the editor(s). Create a new component based on TForm/TFrame/TPanel for the editor(s) you want the user to be able to create multiple instances of. You will have to hand code the creation & deletion of any sub-controls, Setting their properties within your code and assigning values - anything from V_Btn = new TBitBtn(this), V_Btn->Color = clTeal, to V_Btn->OnClick = Close_The_Window. BUT NEVER assign a value to the Name property of any component in the new class and do not set the Name property of the editor once you have created an instance of the editor. Treat the Name property for editor as if it did not exist. After you have created the class and added it to your project the following is valid :
TMyeditor* Editor_01 = new TMyeditor(Main_Form);
TMyeditor* Editor_02 = new TMyeditor(Main_Form);
Editor_01->Parent = Tab_Sheet_Addresses;
Editor_02->Parent = Tab_Sheet_Billing;
The more complex the design concept for your editor the more effort you will undergoe to code the class. However this approach will resolve the "already exists" error.
End of answer.
The following is tangental to the original question as it is an extension of what you may want to further do with your code & I write it to help you along should it be the case. The following allows you to efficiently store/retrieve the editor(s) and its published properties such as position on the user's screen, themes, etc. If you've gone the above route, add the following :
void RegisterClassesWithStreamingSystem(void)
{
// Make sure that as part of the startup
// code TMyEditor is registered
// with the streaming system.
#pragma startup RegisterClassesWithStreamingSystem
Classes::RegisterClass(__classid(TMyEditor));
}
You can now ComponentToString <---> StringToComponent[*1] the editor(s).
You can now create a simple database of each editor saving it [*2] and re-creating the editor(s) at runtime. Saving & Recreating is almost entirely done by the TReader/TWriter objects.
{It is worth while to read about TReader/TWriter which is included in the Delphi help file}
[ Presupposing you have an instances of TMyEditor you want to save called Editor_01 & Editor_02 and
you've created the dataset and assigned it to a TClientDataSet named "CDS" ]
//How to write the Editors
String_Version_Of_Editor = ComponentToString(Editor_01);
CDS->Insert();
CDS->FieldByName("Data")->AsString = String_Version_Of_Editor;
CDS->Post();
String_Version_Of_Editor = ComponentToString(Editor_02);
CDS->Insert();
CDS->FieldByName("Data")->AsString = String_Version_Of_Editor;
CDS->Post();
//How to read, create an instance of, set the Owner of
//(allowing for automatic destruction/deletion
// if desired, Vis-à-vis Let the compiler/runtime package handle that),
//& setting the form's Parent
AnsiString String_Version_Of_Editor;
TWinControl* New_Editor;
String_Version_Of_Editor = CDS->FieldByName("Data")->AsString;
//The next line creates/constructs the new editor
New_Editor = StringToComponent(String_Version_Of_Editor);
//The next line sets the new editor's Owner to Main_Form
//It also assigns Main_Form the responsibility of object cleanup
Main_Form->Insert(New_Editor);
//The next line sets the Editor's Parent causing it to be part of the
//displayed user interface (it has been invisble since creation)
New_Editor->Parent = Tab_Sheet_Addresses;
//Move on to the next editor;
CDS->Next();
String_Version_Of_Editor = CDS->FieldByName("Data")->AsString;
New_Editor = StringToComponent(String_Version_Of_Editor);
Main_Form->Insert(New_Editor);
New_Editor->Parent = Tab_Sheet_Billing;
People who read the above who are astute will have noted that in the above code the New_Editor is of type TWincontrol not TMyEditor - though it likely should have been. However I did this to draw attention to the fact that problematically the TReader object in Delphi which is really doing the work of converting a string to a component object instance creates/constructs any object which has been registered with the streaming class via RegisterClass. In this manner explicit creation of the editor via explicitedly naming it's type is avoided. If thought is given to the design of TMyEditor and its descendents the only change required to the code is to change TWinControl* to TMyEditor* - even that is not required if published properties beyond TWinControl* are not accessed outside the scope of TMyEditor - Example TMyEditor has access to the variables whose values it is editing and does not require this information to be supplied to the editor.(If working from a DataModule, #include the datamodule's header into TMyEditor).
Side Note:
You may have a utility to know what class was read from the database so that you may place the instance where it belongs. To do this #include <typeinfo> into your code.
Example : If you have instances of TMyEditor, TMyEditor_Generation_01, TMyEditor_Generation_02, etc writen to the database the following will allow you to examine the instances read at runtime for placement into the user interface :
if (typeid(New).name() == "TMyEditor *")
New_Editor->Parent = Tab_Sheet_Addresses;
else
if (typeid(New).name() == "TMyEditor_Generation_01 *")
New_Editor->Parent = Tab_Sheet_Billing;
else
if (typeid(New).name() == "TMyEditor_Generation_02 *")
New_Editor->Parent = Tab_Sheet_Other_Editor;
typeid(__).name() will return a string which is the name of the class, in this case will also inculde " *".
The above allows ANY object(s) to be stored in the database and recreated. The entries within the database are not required to be related. The TReader object buried in Delphi's code will decide at runtime what they are and use the correct constructor.
[*1] Note : The ComponentToString and StringToComponent are examples in the delpi/c++ help file.
[*2] Note : What is being saved are the published properties, therefore in your editor class any values you want stored and retrieved which are not already inherited and published should be declared in the __published section of your new class. Those items may also be custom objects, for those you will likely code custom specific methods/functions for the read/write access specifiers in defining the _property. I would suggest translating any complex object into a string value for ease of examining your code while under development.
This question is very similiar to this one. However, the resolution to that question:
Does not seem to apply, or
Are somewhat suspect, and don't seem like a good approach to resolving the problem.
Basically, I'm iterating over a generic list of objects, and inserting them. Using MVC 2, EF 4 with the default code generation.
foreach(Requirement r in requirements)
{
var car = new CustomerAgreementRequirement();
car.CustomerAgreementId = viewModel.Agreement.CustomerAgreementId;
car.RequirementId = r.RequirementId;
_carRepo.Add(car); //Save new record
}
And the Repository.Add() method:
public class BaseRepository<TEntity> : IRepository<TEntity> where TEntity : class
{
private TxRPEntities txDB;
private ObjectSet<TEntity> _objectSet;
public void Add(TEntity entity)
{
SetUpdateParams(entity);
_objectSet.AddObject(entity);
txDB.SaveChanges();
}
I should note that I've been successfully using the Add() method throughout my code for single inserts; this is the first time I've tried to use it to iteratively insert a group of objects.
The error:
System.InvalidOperationException: The changes to the database were committed successfully, but an error occurred while updating the object context. The ObjectContext might be in an inconsistent state. Inner exception message: AcceptChanges cannot continue because the object's key values conflict with another object in the ObjectStateManager. Make sure that the key values are unique before calling AcceptChanges.
As stated in the prior question, the EntityKey is set to True, StoreGeneratedPattern = Identity. The actual table that is being inserted into is a relationship table, in that it is comprised of an identity field and two foreign key fields. The error always occurs on the second insert, regardless of whether that specific entity has been inserted before or not, and I can confirm that the values are always different, no key conflicts as far as the database is concerned. My suspicion is that it has something to do with the temporary entitykey that gets set prior to the actual insert, but I don't know how to confirm that, nor do I know how to resolve it.
My gut feeling is that the solution in the prior question, to set the SaveOptions to None, would not be the best solution. (See prior discussion here)
I've had this issue with my repository using a loop as well and thought that it might be caused by some weird race-like condition. What I've done is refactor out a UnitOfWork class, so that the repository.add() method is strictly adding to the database, but not storing the context. Thus, the repository is only responsible for the collection itself, and every operation on that collection happens in the scope of the unit of work.
The issue there is that: In a loop, you run out of memory damn fast with EF4. So you do need to store the changes periodically, I just don't store after every save.
public class BaseRepository : IRepository where TEntity : class
{
private TxRPEntities txDB;
private ObjectSet _objectSet;
public void Add(TEntity entity)
{
SetUpdateParams(entity);
_objectSet.AddObject(entity);
}
public void Save()
{
txDB.SaveChanges();
}
Then you can do something like
foreach(Requirement r in requirements)
{
var car = new CustomerAgreementRequirement();
car.CustomerAgreementId = viewModel.Agreement.CustomerAgreementId;
car.RequirementId = r.RequirementId;
_carRepo.Add(car); //Save new record
if (some number limiting condition if you have thousands)
_carRepo.Save(); // To save periodically and clear memory
}
_carRepo.Save();
Note: I don't really like this solution, but I hunted around to try to find why things break in a loop when they work elsewhere, and that's the best I came up with.
We have had some odd collision issues if the entity is not added to the context directly after being created (before doing any assignments). The only time I've noticed the issue is when adding objects in a loop.
Try adding the newed up entity to the context, do the assignments, then save the context. Also, you don't need to save the context each time you add a new entity unless you absolutely need the primary key.
i'm trying to create some domain objects from xml.
class A {
String name
}
class B {
A a
int something
}
i first created an instance of A,and flushed. when creating B, first map the available attributes.
def b = new B(xml.attributes())
this would map 'something' correctly, but not the object type A. So, I retrieve the instance of A and add like
b.a = A.findByA("id of a")
I could see the object b is constructed (both fields filled in) in the debugger, but it doesn't persist on save(flush:true).
What is wrong in the above assignemt, or should use the id instead (b.a.id = ..)
How can I see what is going wrong in the log file? which trace needs to be enabled. I enabled there in config file
trace 'org.hibernate.SQL', 'org.hibernate.type' (which gives the sql trace for insert, select etc. But not for the above scenario, may be because it doesn't reach to hibernate).
Any pointer, highly appreciated.. thanks.
I would wager to guess that your save() is failing validation. You can add save(failOnError:true) to throw an exception when the validation fails, or add the following code to print each of the errors:
b.errors.allErrors.each {
println it
}
With the debugging tip from Rich, I could narrow down the problem... had to rename the attribute to prevent auto mapping. See a similar issue, and response at http://grails.1312388.n4.nabble.com/domain-controller-and-Failed-to-convert-property-value-of-type-problem-td1357947.html
To create association you must pass an object of A
new B(a:A.get(id))
or
B b = new B()
b.a = A.get(id)
Where id must be Integer or Long
Either I miss some context but class A doesn't have method findByA. There is no such A attribute for class A. Suggest you to use method get for strict findings.