I have a very simple row that I'm inserting using Entity, which I do like so:
var context = GetEntityContext();
SOMEPOCO newobj = new SOMEPOCO
{
Data = data
};
context.SOMEOBJECTS.Add(newobj);
context.SaveChanges();
return newobj.ID;
And newobj.ID (the auto-incremented primary key) is indeed populated. No errors are raised or exceptions thrown. But when I go to SQL Management Studio and query for items or look it up in code, it doesn't show up. But if I manually make an entry in the DB, it increments the primary key as though the previous failed entry were there.
What could be causing this?
Thanks.
Related
See Datasource Paging Issue (Revised)
for the original question.
Markus, you were kind enough to help with out with the issue of incorporating a record count into a query using a calculated datasource. I have a search form with 15 widgets - a mix of date ranges, dropdowns, text values and ._contains, ._equals, ._greaterThanOrEquals, ._lessThanOrEquals, etc.
I have tested this extensively against mySQL SQL code and it works fine.
I have now added a 16th parameter PropertyNames, which is a list with binding #datasource.query.filters.Property.PropertyName._in and Options blank. The widget on the form is hidden because it is only used for additional filtering.
Logic such as the following is used, such that a particular logged-in user can only view their own properties. So if they perform a search and the Property is not specified we do:-
if (params.param_Property === null && canViewAllRecords === false) {
console.log(params.param_PropertyNames); // correct output
ds.filters.Property.PropertyName._in = params.param_PropertyNames;
}
The record count (records.length) is correct, and if I for loop through the array of records the record set is correct.
However, on the results page the table displays a larger resultset which omits the PropertyNames filter. So if I was to search on Status 'Open' (mySQL results 50) and then I add a single value ['Property Name London SW45'] for params.param_PropertyNames the record count is 6, the records array is 6 but the datasource display is 50. So the datasource is not filtering on the property array.
Initially I tried without adding the additional parameter and form widget and just using code such as
if (params.param_Property === null && canViewAllRecords === false) {
console.log(params.param_PropertyNames); // correct output
ds.filters.Property.PropertyName._in = properties; // an array of
properties to filter out
}
But this didn't work, hence the idea of adding a form widget and an additional parameter to the calculated recordcount datasource.
If I inspect at query.parameters then I see:-
"param_Status": "Open",
"param_PropertyNames": ["Property Name London SW45"],
If I inspect query.filters:-
name=param_Status, value=Open
name=param_PropertyNames, value=[]}]}
It looks as though the filter isn't set. Even hard coding
ds.filters.Property.PropertyName._in = ['Property Name London SW45'],
I get the same reuslt.
Have you got any idea what would be causing this issue and what I can do for a workaround ?
Using a server side solution I would suggest editing both your SQL datasource query script (server side) that is supposed to filter by this property list and including the same code in your server side script for your calculated Count datasource. The code would look something like this, not knowing your exact details:
var subquery = app.models.Directory.newQuery();
subquery.filters.PrimaryEmail._equals = Session.getActiveUser().getEmail();
subquery.prefetch.Property._add();
var results = subquery.run();
if(!results[0].CanViewAllRecords) {
query.filters.Property.PropertyName._in = results[0].Property.map(function(i) {return i.PropertyName;});
}
By adding this code you are filtering your directory by your current user and prefetching the Property relation table, then you set the filter only if your user canviewallRecords is false and use JS map function to create an array of the PropertyName field in the Property table. As I stated, your code may not be exactly the same depending on how you have to retrieve your user canviewallrecords property and then of course I don't know your relation between user and Property table either, is it one-to-many or other. But this should give you an idea how to implement this on server side.
I have a window in a Qt application using PostgreSQL 9.3 database. The window is a form used do display, edit and insert new data. t looks like that:
I have data from 3 sql tables in that view. the tables are related with foreign keys:
contractors (main table) - mapped to "personal data" section
contacts (has foreign key to contractors.ID)
addresses (has foreign key to contractors.ID)
So - in my window's class I have 3 main models (+ 2 proxy models to transpose tables in "personal data" an "address data" sections). I use QSqlTableModel for theese sesctions, and a QSqlRelationalTableModel for contactData section. when opening that window "normally" (to view some contractor), i simply pass contractor's ID to the constructor and store it in proper variable. Also, I call the QSqlTableModel::​setFilter(const QString & filter) method for each of the models, and set the proper filtering. When opening that window in "add new" mode i simply pass a "-1" or "0" value to the ID variable, so no data gets loaded to the model.
All 3 models have QSqlTableModel::OnManualSubmit editStrategy. When saving the data (triggered by clicking a proper button), I start a transaction. And then I submit models one-by-one. personalData model gets submitted first, as I need to obtain it's PK after insert (to set in the FK fields in other models).
When submitting of the model fails, I show a messageBox with the QSqlError content, rollback the transaction and return from the method.
When I have an error on the first model being processed - no problem, as nothing was inserted. But when the first model is saved, but the second or third fails - there is a little problem. So I rollback the transacion as before, and return from the function. But after correcting the data and submitting it again - the first model is not trying to submit - as it doesn't know that there was a rollback, and the data needs to be inserted again. What would be a good way to notice such a model, that it needs to be submited once again?
At the moment I ended up with something like that:
void kontrahenciSubWin::on_btnContractorAdd_clicked() {
//QStringList errorList; // when error occurs in one model - whole transacion gets broken, so no need for a list
QString error;
QSqlDatabase db = QSqlDatabase::database();
//backup the data - in case something fails and we have to rollback the transaction
QSqlRecord personalDataModelrec = personalDataModel->record(0); // always one row. will get erased by SubmitAll, as no filter is set, because I don't have its ID.
QList<QSqlRecord> contactDataModelRecList;
for (int i = 0 ; i< contactDataModel->rowCount(); i++) {
contactDataModelRecList.append( contactDataModel->record(i) );
}
QList<QSqlRecord> addressDataModelRecList;
for (int i = 0 ; i< addressDataModel->rowCount(); i++) {
addressDataModelRecList.append( addressDataModel->record(i) );
}
db.transaction();
if ( personalDataModel->isDirty() && error.isEmpty() ) {
if (!personalDataModel->submitAll()) //submitAll calls select() on the model, which destroys the data as the filter is invalid ("where ID = -1")
//errorList.append( personalDataModel->lastError().databaseText() );
error = personalDataModel->lastError().databaseText();
else {
kontrahentid = personalDataModel->query().lastInsertId().toInt(); //only here can I fetch ID
setFilter(ALL); //and pass it to the models
}
}
if ( contactDataModel->isDirty() && error.isEmpty() )
if (!contactDataModel->submitAll()) //slot on_contactDataModel_beforeInsert() sets FK field
//errorList.append( contactDataModel->lastError().databaseText() );
error = contactDataModel->lastError().databaseText();
if ( addressDataModel->isDirty() && error.isEmpty() )
if (!addressDataModel->submitAll()) //slot on_addressDataModel_beforeInsert() sets FK field
//errorList.append( addressDataModel->lastError().databaseText() );
error = addressDataModel->lastError().databaseText();
//if (!errorList.isEmpty()) {
// QMessageBox::critical(this, tr("Data was not saved!"), tr("The following errors occured:") + " \n" + errorList.join("\n"));
if (!error.isEmpty()) {
QMessageBox::critical(this, tr("Data was not saved!"), tr("The following errors occured:") + " \n" + error);
db.rollback();
personalDataModel->clear();
contactDataModel->clear();
addressDataModel->clear();
initModel(ALL); //re-init models: set table and so on.
//re-add data to the models - backup comes handy
personalDataModel->insertRecord(-1, personalDataModelrec);
for (QList<QSqlRecord>::iterator it = contactDataModelRecList.begin(); it != contactDataModelRecList.end(); it++) {
contactDataModel->insertRecord(-1, *it);
}
for (QList<QSqlRecord>::iterator it = addressDataModelRecList.begin(); it != addressDataModelRecList.end(); it++) {
addressDataModel->insertRecord(-1, *it);
}
return;
}
db.commit();
isInEditMode = false;
handleGUIOnEditModeChange();
}
Does anyone have a better idea? I doubt if it's possible to ommit backing-up the records before trying to insert them. But maybe there is a better way to "re-add" them to the model? I tried to use "setRecord", and "remoweRows" & "insertRecord" combo, but no luck. Resetting the whole model seems easiest (I only need to re-init it, as it loses table, filter, sorting and everything else when cleared)
I suggest you to use a function written in the language PLPGSQL. It has one transaction between BEGIN and END. If it goes wrong at a certain point of the code then will it rollback all data flawlessly.
What you are doing now is not a good design, because you handle the control over a certain functionality (rollback) to an external system with regard to the rollback (it is happening in the database). The external system is not designed to do that, while the database on the contrairy is created and designed for dealing with rollbacks and transactions. It is very good at it. Rebuilding and reinventing this functionality, which is quite complex, outside the database is asking for a lot of trouble. You will never get the same flawless rollback handling as you will have using functions within the database.
Let each system do what it can do best.
I have met your problem before and had the same line of thought to work this problem out using Hibernate in my case. Until I stepped back from my efforts and re-evaluated the situation.
There are three teams working on the rollback mechanism of a database:
1. the men and women who are writing the source code of the database itself,
2. the men and women who are writing the Hibernate code, and
3. me.
The first team is dedicated to the creation of a good rollback mechanism. If they fail, they have a bad product. They succeeded. The second team is dedicated to the creation of a good rollback mechanism. Their product is not failing when it is not working in very complex situations.
The last team, me, is not dedicated to this problem. Who am I to write a better solution then the people of team 2 or team 1 based on the work of team 2 who were not able to get it to the level of team 1?
That is when I decided to use database functions instead.
I'm newbie in SQLite.
I would like to query my SQLite database to get multiple rows.
When I add a new item in my local database I call this method Add:
public bool Add<T>(string key, T value)
{
return this.Insert(new SQliteCacheTable(key, this.GetBytes(value))) == 1;
}
_simpleCache.Add("favorite_1", data1);
_simpleCache.Add("favorite_2", data2);
_simpleCache.Add("favorite_3", data2);
Then,
I would like to retrieve from local database all entries where key starts with "favorite_"
to returns all objects in the database which are "favorite" objects.
I'm experienced in Linq, and I would like to do something like this:
IEnumerable<Element> = repository.Find((element) => element.Key.StartWith("favorite_"))
In the SQLiteConnection class there is a method like this:
SQLite.Net.SQLiteConnection.Find<T>(System.Linq.Expressions.Expression<System.Func<T,bool>>)
But I would like the same with in returns a collection IEnumerable<T>.
Can you help me please?
Thank you.
Jool
You have to build your query on the table itself, not the connection:
Assuming:
SQLiteConnection repository;
Then the code would look like:
var favorites = repository.Table<SQliteCacheTable>().Where(item => item.StartsWith("favorite_"));
The favorites variable is of type TableQuery<SQliteCacheTable> though, so it does not yet contain your data. The execution of the actual SQL query will be deferred until you try to access the results (by enumerating with foreach or converting to a list with ToList, for example).
To actually observe what's going on on the database, you can turn on tracing in sqlite-net, by setting repository.Trace = true on your SQLiteConnection object.
Finally, it's worth mentioning that you can also use the C# query syntax on TableQuery<T> objects, if your comfortable with it. So your query could become:
var favorites = from item in repository.Table<SQliteCacheTable>()
where item.StartsWith("favorite_")
select item;
I am using ASP.NET MVC2 in Visual Studio 2008. I believe the SQL Server is 2005.
I have two tables: EquipmentInventory and EquipmentRequested
EquipmentInventory has a primary key
of sCode
EquipmentRequested has a
foreign key called sCode based upon
sCode in EquipmentInventory.
I am trying the following code (lots of non-relevent code removed):
try
{
EChODatabaseConnection myDB = new EChODatabaseConnection();
//this section of code works fine. The data shows up in the database as expected
foreach (var equip in oldData.RequestList)
{
if (equip.iCount > 0)
{
dbEquipmentInventory dumbEquip = new dbEquipmentInventory();
dumbEquip.sCode = equip.sCodePrefix + newRequest.iRequestID + oldData.sRequestor;
myDB.AddTodbEquipmentInventorySet(dumbEquip);
}
}
myDB.SaveChanges(); //save this out immediately so we can add in new requests
//this code runs fine
foreach (var equip in oldData.RequestList)
{
if (equip.iCount > 0)
{
dbEquipmentRequested reqEquip = new dbEquipmentRequested();
reqEquip.sCode = equip.sCodePrefix + newRequest.iRequestID + oldData.sRequestor;
myDB.AddTodbEquipmentRequestedSet(reqEquip);
}
}
//but when I try to save the above result, I get an error
myDB.SaveChanges();
oldData is passed into the function. newRequest is the result of adding to a "non-related" table. newRequest.iRequestID does have a value.
In looking at the reqEquip is the watch window, I do notice that EquipInventory is null.
The error message I receive is:
"Entities in 'EChODatabaseConnection.dbEquipmentRequestedSet' participate in the 'FK_EquipmentRequested_EquipmentInventory_sCode' relationship. 0 related 'EquipmentInventory' were found. 1 'EquipmentInventory' is expected."
Obviously I'm doing something wrong but thus far, I can not seem to find where I am having a problem.
Anyone have some hints on how to properly insert a record into a table that has a foreign key reference?
UPDATE:
I am using the Data Entity Framework.
UPDATE:
Thanks to Rob's answer, I was able to figure out my error.
As Rob mentioned, I needed to set my reference for the foreign key.
My coding result looks like:
foreach (var equip in oldData.RequestList)
{
if (equip.iCount > 0)
{
dbEquipmentInventory dumbEquip = new dbEquipmentInventory();
dumbEquip.sCode = equip.sCodePrefix + newRequest.iRequestID + oldData.sRequestor;
myDB.AddTodbEquipmentInventorySet(dumbEquip);
//add in our actual request items
dbEquipmentRequested reqEquip = new dbEquipmentRequested();
reqEquip.EquipmentInventory = dumbEquip;
myDB.AddTodbEquipmentRequestedSet(reqEquip);
}
}
myDB.SaveChanges();
Does anyone see a better method for doing this?
What are you using as an ORM? I believe that regardless of which one you're using, you could use the foreign key handling of most ORMs to handle this for you. For example, you make a new dumbEquip, don't do the immediate save. Do your dbEquipmentRequested reqEquip = new dbEquipmentRequested(); and add the data to it and then say dumbEquip.dbEquipmentRequested.Add(reqEquip). Then save the record and the ORM should save the records in the correct order required for the FK and even enter the FK ID into the reqEquip record.
So I'm starting out with EF on my website (C#) and Ive run into a bit of a snag. A user can either create or modify data and they will do that with the selection screen (page 1). If a user selects to create new data, I will perform the following code:
Program newProg = new Program();
using (DatabaseEntities context = new DatabaseEntities())
{
Guid id = new Guid(list.SelectedValue);
var itemString = from item in context.Set where item.Id == id select item;
Item selectedItem = itemString.ToList()[0];
newProg.Items.Add(selectedItem);
context.AddToProgramSet(newProg);
context.Detach(newProg);
}
Pretty much creating a new instance of the 'Program' which will be passed along each user control until the user is ready to submit to the database. At that point the following code will be executed:
using (DatabaseEntities context = new DatabaseEntities())
{
context.AddToProgramSet(this.SummaryControl.SelectedProgram);
context.SaveChanges();
}
Unfortunately when I get there, I receive the following message:
The object cannot be added to the ObjectStateManager because it already has an EntityKey. Use ObjectContext.Attach to attach an object that has an existing key.
at this line:
context.AddToProgramSet(this.SummaryControl.SelectedProgram);
Also, when I add the following line prior to the previous:
context.Attach(this.SummaryControl.SelectedProgram);
I get this error:
An object with a null EntityKey value cannot be attached to an object context.
Any help would be greatly appreciated. Thanks.
The root cause of this error is that you are attempting to add an Entity as a new Entity that already has its primary key set.
At what point do you add the Entities to your SummaryControl? Your first code snippet shows you adding the Entity:
...
newProg.Items.Add(selectedItem);
context.AddToProgramSet(newProg);
context.Detach(newProg);
...
Then you appear to add it again:
using (DatabaseEntities context = new DatabaseEntities())
{
context.AddToProgramSet(this.SummaryControl.SelectedProgram);
context.SaveChanges();
}
If newProg and this.SummaryControl.SelectedProgram are the same Entity, you've attempted to add it twice. Remove the context.AddToProgramSet(newProg); from the first snippet, do you work on the Entity, then add it to the ProgramSet.
Dave is right that the root cause is that the entity already has a primary key.
One thing that you do not show in your code is how:
Program newProg = new Program();
Becomes:
this.SummaryControl.SelectedProgram
One way that you could fix it is by saving newProg to the database before you start adding Items to it.