I am sorry if it has already been answered but I can't find any solution. Here is my (little) problem. Also all my apologies if the terms I use are approximate, I am far from being a skilled C# developer
Note that I think my problem is similar to this one Entity Framework validation error for missing field, but it's not missing?
I have a table "Tweets" with a tweet_id field (bigint) which is my primary key.
I use the following class to load the table :
class TwitterDbContext : DbContext
{
public TwitterDbContext() : base("Twitter")
{
}
public DbSet<Stream> Streams { get; set; }
public DbSet<StreamParameter> StreamParameters { get; set; }
public DbSet<Tweet> Tweets { get; set; }
}
public class Tweet
{
public Tweet()
{
}
[Key]
public long tweet_id { get; set; }
public string tweet { get; set; }
public long creator { get; set; }
public double latitude { get; set; }
public double longitude { get; set; }
public string language { get; set; }
public DateTime created_at { get; set; }
public DateTime registered_at { get; set; }
public long? in_reply_to { get; set; }
public bool retweeted { get; set; }
}
I have an other class to store within the code execution all the fields used by the Tweet table. For the need here, let's imagine I manually create it that way
private void Test_Button_Click(object sender, RoutedEventArgs e)
{
Twts twtReceived = new Twts();
twtReceived.tweet_id = 1;
twtReceived.tweet = "test";
twtReceived.creator = 1;
twtReceived.latitude = -1;
twtReceived.longitude = -1;
twtReceived.language = "a";
twtReceived.created_at = DateTime.Now;
twtReceived.registered_at = DateTime.Now;
twtReceived.in_reply_to = 1;
twtReceived.retweeted = true;
AddTweet(twtReceived);
}
Now here is the AddTweet method
static public void AddTweet(Twts twtReceived)
{
try
{
// update the tweet data in the database
using (var TwitterDb = new TwitterDbContext())
{
Tweet twt = new Tweet()
{
tweet_id = twtReceived.tweet_id,
tweet = twtReceived.tweet,
creator = twtReceived.creator,
longitude = twtReceived.longitude,
latitude = twtReceived.latitude,
language = twtReceived.language,
created_at = twtReceived.created_at,
registered_at = twtReceived.registered_at,
in_reply_to = twtReceived.in_reply_to,
retweeted = twtReceived.retweeted
};
TwitterDb.Tweets.Add(twt);
TwitterDb.SaveChanges();
}
}
catch(Exception ex)
{
MessageBox.Show(ex.InnerException.ToString());
}
}
I constantly have the same error message:
Cannot insert the value NULL into column 'tweet_id', table
'Twitter.dbo.Tweets'; column does not allow nulls. INSERT fails.
The thing is that when I spy on "TwitterDb.Tweets.Local" after TwitterDb.Tweets.Add(twt); I correctly have tweet_id set to 1.
Any idea where is the issue?
Try marking your tweet_id field with following (instead of just [Key]), if this is a primary key column where you want to provide values yourself
[Required, Key, DatabaseGenerated(DatabaseGeneratedOption.None)]
If it is an auto-increment, then remove explicit assignments to this field and mark it as 'Identity' instead:
[Required, Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
Related
eWhy is my Icollection foreign key always blank I have a foreign table called photos which I have created using the Icollection. Im using ef core 3.1.7 and asp.net core 3.1 how does one get the file attachments VesselsId not to be null
Basically one vessel can have many photos but their could also be many vessels.
public class Vessels {
public int Id { get; set; }
[StringLength(400)]
public string Name { get; set; }
public string FlagName { get; set; }
public ICollection<FileAttachments> PhotosAttachments { get; set; }
}
This is the file attachments
public class FileAttachments {
public int Id { get; set; }
public string Title { get; set; }
public string File { set; get; }
}
In where I Wish to display the photos their blank I use the include statement to try and include them in my query.
var vessels = await _context.Vessels.Where(w=>w.Id==id).Include(c=>c.PhotosAttachments).FirstAsync();
But If I look here it will show PhotosAttachments being of null when I look at the field value sure enough its sitting there null.
I think i need to do something here but im not sure as to what
protected override void OnModelCreating(ModelBuilder modelBuilder) {
base.OnModelCreating(modelBuilder);
}
Edit 2
Basically i have a generic Upload Files method as such which is called via the submit button
[HttpPost]
public async Task<IActionResult> UploadFiles(List<IFormFile> FormFile, int UploadArea, int PoiId, int VesselId) {
FileAttachments attachments = new FileAttachments {
DocumentPath = filePath,
UploadAreaId = UploadArea,
CaseId = resultCaseId,
FullPath = savedFileName,
FileSize = infoFile.Length,
OrignalFileName = fileAttachments.FileName,
FileAttachmentType = fileAttachmentType,
TennantId = await GetCurrentTennantId(),
Extension = infoFile.Extension.Replace(".", "").ToLower(),
UploadedBy = caseOfficer.Id,
CreatedDate = DateTime.Now,
File = uniqueFilename,
ContentType = fileAttachments.ContentType,
isActive = true,
isDeleted = false
};
if (PoiId != 0) {
attachments.PoiID= PoiId;
}
if (VesselId != 0) {
attachments.VesselId = VesselId;
}
_context.Add(attachments);
await _context.SaveChangesAsync();
}
There is some confusion above i am using to store something else the
collection does not create this field it creates VesselsId with the
extra s this is what is not being filled in.
public int? VesselId { get; set; }
The collection creates this field
Add relation to FileAttachments model like this
public class FileAttachments {
...
[ForeignKey("Vessels")]
public int? VesselId { get; set; }
public Vessels Vessels { get; set; }
}
I am using this example from Umbraco docs and when i try to save values to the database table i am getting this error:
Cannot insert the value NULL into column 'Id', table 'petapoco.dbo.BlogComments'; column does not allow nulls. INSERT fails. The statement has been terminated.
Also, after table is created and i check it in database, I can see that primary key and autoincrement option is not set for id field.
And this is how i insert values:
public class Class1 : IUserComposer
{
public void Compose(Composition composition)
{
composition.Components().Append<SubscribeToContentServiceSavingComponent>();
}
public class SubscribeToContentServiceSavingComponent : IComponent
{
public void Initialize()
{
MemberService.Saved += MemberService_Saving;
}
public void Terminate()
{
}
private void MemberService_Saving(IMemberService sender, SaveEventArgs<IMember> e)
{
foreach (IMember member in e.SavedEntities)
{
var blogPostToAdd = new BlogCommentSchema();
blogPostToAdd.BlogPostUmbracoId = member.Id;
blogPostToAdd.Name = member.Name;
blogPostToAdd.Email = member.Name;
blogPostToAdd.Website = member.Name;
blogPostToAdd.Message = member.Name;
using (var scope = Current.ScopeProvider.CreateScope(autoComplete:true))
{
var database = scope.Database;
// use database
scope.Database.Insert<BlogCommentSchema>(blogPostToAdd);
scope.Complete();
}
}
}
}
}
Good guy on Umbraco forum solved my problem. This is the missing part in my class:
[PrimaryKeyColumn(AutoIncrement = true, IdentitySeed = 1)]
So my class finally should look like this:
[TableName("BlogComments")]
[PrimaryKey("Id", AutoIncrement = true)]
[ExplicitColumns]
public class BlogCommentSchema
{
[PrimaryKeyColumn(AutoIncrement = true, IdentitySeed = 1)]
[Column("Id")]
public int Id { get; set; }
[Column("BlogPostUmbracoId")]
public int BlogPostUmbracoId { get; set; }
[Column("Name")]
public string Name { get; set; }
[Column("Email")]
public string Email { get; set; }
[Column("Website")]
public string Website { get; set; }
[Column("Message")]
[SpecialDbType(SpecialDbTypes.NTEXT)]
public string Message { get; set; }
}
}
I have an Entity MVC app with a code-first database. I need to produce a search box to search between 2 dates and return the records between those dates.
I will call the method with jQuery/ajax and render the results in a table.
I've tried writing an API, with no success. I am not even sure if this is the correct way to go about it?
namespace Areometrex_Leaflet.Models
{
[Table ("Flight_Lines")]
public class Flight_line
{
[Key]
public string Swath_name { get; set; }
public string Flight_name { get; set; }
public string Swath_record { get; set; }
public string Flight_date { get; set; }
public decimal Start_lat { get; set; }
public decimal Start_long { get; set; }
public decimal End_lat { get; set; }
public decimal End_long { get; set; }
public decimal Altitude { get; set; }
public DateTime Time_start { get; set; }
public DateTime Time_end { get; set; }
public string Sensor { get; set; }
}
public class FlightLineContext : DbContext
{
public DbSet<Flight_line> Flight_Lines { get; set; }
}
}
This is my model that holds the objects in the database. I need to search the "Flight_date" property, that is held in my DB in this following format as an "nvarchar" :
17/11/2018 11:09:18 PM
My current API looks something like this:
[HttpPost]
public IEnumerable<Flight_line> SearchFlight_Line()
{
string start, end;
var rc = RequestContext;
var data = rc.Url.Request.GetQueryNameValuePairs();
{
start = data.FirstOrDefault().Value ?? string.Empty;
end = data.LastOrDefault().Value ?? string.Empty;
}
//db format: 17/11/2018 11:22:56 PM
var s = DateTime.Parse(start);
var flightSearch = new List<Flight_line>();
using (_context)
{
var sql = $"SELECT * FROM Flight_Lines WHERE Flight_Date BETWEEN '{start}' AND '{end}'";
flightSearch = _context.Flight_Lines.SqlQuery(sql).ToList<Flight_line>();
}
return flightSearch;
}
Ideally, I want to call this API with jquery/Ajax and return results to be displayed in an MVC view. My guess is that this is dead easy, but I am only learning and I'm running out of ideas. I would have thought this was really simple, but I am struggling to find the answers I am looking for online, which leads me to believe perhaps I am doing it wrong?
First of all, don't save dates as string in your database, you will just have problems later on.
Instead of:
public string Flight_date { get; set; }
Set it up as DateTime:
public DateTime Flight_date { get; set; }
As far as the query for searching flights go, you can try this. This will return a list of "Flight_line" objects which you can then return wherever you need.
DateTime start = DateTime.Now;
DateTime end = DateTime.Now.AddDays(7);
var flights = _context.Flight_line.Where(f => f.Flight_date >= start && f.Flight_date <= end).ToList();
I have this error during save on update data in my mongo db.
this is erorr:
Save can only be used with documents that have an Id.
this is my model:
public ModelKorisici () { }
[BsonId(IdGenerator = typeof(CombGuidGenerator))] // posajvljivaa se greška kod BSON tipa podataka kod ID-a,preuzoteo s dokumentacije drivera 1.5
public Guid Id { get; set; }
[BsonElement("ime")]
public string ime { get; set; }
[BsonElement("prezime")]
public string prezime { get; set; }
[BsonElement("lozinka")]
public string lozinka { get; set; }
[BsonElement("email")]
public string email { get; set; }
[BsonElement("kor_ime")]
public string kor_ime { get; set; }
[BsonElement("uloga")]
public string uloga { get; set; }
}
My code for update is here:
public void urediKorisnika(ModelKorisici korisnik)
{
MongoCollection<ModelKorisici> kljenti = GetTasksCollection();
kljenti.Save(kljenti);
}
Can anyone help?
I'm not sure what are you trying to do but your error is in following code block
public void urediKorisnika(ModelKorisici korisnik)
{
MongoCollection<ModelKorisici> kljenti = GetTasksCollection();
kljenti.Save(kljenti);
}
Here are you trying to store collection to itself. I believe GetTasksCollection() return collection from MongoDB and then you are trying to store it into itself again. see kljenti.Save(kljenti);
You need to create instance of ModelKorisici and save it into kljenti
Your code should look something like:
public void urediKorisnika(ModelKorisici korisnik)
{
MongoCollection<ModelKorisici> kljenti = GetTasksCollection();
var model = new ModelKorisici();
model.ime = ...
...
kljenti.Save(model);
}
Hopefully, the question header is clear enough to tell that I'm trying to read an Access file and upload the data to the database but checking at first whether the data already exists or not in the database.
I receive a daily report from a third-party company in Access file. I'm trying to create a windows service that will check for the file every morning, and if the new file exist, then it'll read and upload the data to the database. I'm trying to use Entity Framework. I read the article on Navigation Property, but I'm still confused on that; I never used navigation property before. Here are my models:
[Table("ClaimsTable")]
public partial class ClaimsTable
{
[Key]
[DatabaseGenerated(System.ComponentModel.DataAnnotations.Schema.DatabaseGeneratedOption.Identity)]
public int ClaimsID { get; set; }
public string EOPAID { get; set; }
public string AuthID { get; set; }
public string PAStatus { get; set; }
public string UserName { get; set; }
[DataType(DataType.Date)]
public DateTime EffectiveDate { get; set; }
[DataType(DataType.Date)]
public DateTime EndDate { get; set; }
public string RecordType { get; set; }
public int RxID { get; set; }
public int MemberID { get; set; }
public int PrescriberID { get; set; }
public string EditNumber { get; set; }
public string OriginSource { get; set; }
public string OriginMethod { get; set; }
/*
[ForeignKey("RxID")]
public virtual RxTable Prescription { get; set; }
[ForeignKey("MemberID")]
public virtual MembersTable Member { get; set; }
[ForeignKey("PrescriberID")]
public virtual PrescribersTable Prescriber { get; set; }
*/
}
...
[Table("MembersTable")]
public partial class MembersTable
{
[Key]
[DatabaseGenerated(System.ComponentModel.DataAnnotations.Schema.DatabaseGeneratedOption.Identity)]
public int MemberID { get; set; }
[DataType(DataType.Date), Display(Name= "Date of Birth"), DisplayFormat(DataFormatString="{0:mm/dd/yyyy}", ApplyFormatInEditMode=true)]
public DateTime DateofBirth { get; set; }
public string CardholderID { get; set; }
public string MemberFirstName { get; set; }
public string MemberLastName { get; set; }
//public virtual ICollection<AddressTable> Address { get; set; }
}
...
[Table("PrescribersTable")]
public partial class PrescribersTable
{
[Key]
[DatabaseGenerated(System.ComponentModel.DataAnnotations.Schema.DatabaseGeneratedOption.Identity)]
public int PrescriberID { get; set; }
public string NPI { get; set; }
public string PrescriberFirstName { get; set; }
public string PrescriberLastName { get; set; }
public string PhysicianType { get; set; }
//public ICollection<AddressTable> Address { get; set; }
}
....
using(OleDbConnection conn = new OleDbConnection(strDSN))
{
OleDbDataReader reader = null;
OleDbCommand command = new OleDbCommand("Select * from table", conn);
try
{
conn.Open();
}
catch(OleDbException o)
{
return o.Message;
}
reader = command.ExecuteReader();
List<ClaimsTable> Claim = new List<ClaimsTable>();
List<PrescribersTable> PrescriberInDB = new List<PrescribersTable>();
List<MembersTable> MembersInDB = new List<MembersTable>();
while(reader.Read())
{
PrescriberInDB = context.Prescribers.ToList();
MembersInDB = context.Members.ToList();
//CREATE LOCAL VARIABLE
string recordType = //check if the member and the prescriber exist in the database
int prescriberID = 0;
int prodID = 0;
int memberID = 0;
int drugID = 0;
int RxID = 0;
int claimID = 0;
//check if the member and the prescriber exist in the object before inserted into the database.
//the data will be uploaded to the database in bulk
//int newPrescriberID = Prescriber.Where(x => x.PrescriberFirstName == reader["Prescriber First Name"] && x.PrescriberLastName == reader["Prescriber Last Name"] && x.NPI == reader["Prescribing Physician"]).Select(x => x.PrescriberID).FirstOrDefault();
//int newMemberID = Member.Where(x => x.MemberFirstName == reader["Member First Name"] && x.MemberLastName == reader["Member Last Name"] && x.CardholderID == reader["CardhHolder"]).Select(x => x.MemberID).FirstOrDefault();
//insert the data if it doesn't exist
if(!PresciberExist(prescriberFirstName, prescriberLastName, npi, PrescriberInDB))
{
var prescriber = new PrescribersTable()
{
PrescriberFirstName = prescriberFirstName,
PrescriberLastName = prescriberLastName,
NPI = npi,
PhysicianType = physicianType
};
context.Prescribers.Add(prescriber);
context.SaveChanges();
prescriberID = GetPrescriberID(prescriberFirstName, prescriberLastName, physicianType, PrescriberInDB);
}
if(!MemberExist(memberFirstName, memberLastName, cardholderID, MembersInDB))
{
var member = new MembersTable()
{
MemberFirstName = memberFirstName,
MemberLastName = memberLastName,
CardholderID = cardholderID,
DateofBirth = dob
};
context.Members.Add(member);
context.SaveChanges();
memberID = GetMemberID(memberFirstName, memberLastName, cardholderID, MembersInDB);
}
}
}
return "Done uploading";
}
private bool MemberExist(string memberFirstName, string memberLastName, string cardholderID, List<MembersTable> MembersInDB)
{
return MembersInDB.Exists(x => x.MemberFirstName == memberFirstName && x.MemberLastName == memberLastName && x.CardholderID == cardholderID);
}
private bool PresciberExist(string prescriberFirstName, string prescriberLastName, string npi, List<PrescribersTable> PrescriberInDB)
{
return PrescriberInDB.Exists(x => x.PrescriberFirstName == prescriberFirstName && x.PrescriberLastName == prescriberLastName && x.NPI == npi);
}
The access database contains sensitive information, so I won't be able to add those data as an example. But here's a made up data for test. The data contains claims of patients.
Now, because there are many drugs and many claims for the same patient, and many patients for a prescriber.. I broke the database as it's shown above. Needs improvement? I welcome suggestion. The reason I did this is because I don't want my database to have repeated records which will make managing really troubling. This way, I'll have unique members in memberstable, unique prescribers in prescriberstable and so on and so forth.
The challenge I'm facing is that when I read the data from the access database, I'm assuming it reads row-wise. The code should first check the database whether the member exist or not. If it does, then get the member id which is an identity column. If it doesn't, then it should insert the member's info only, and then get the memberID. Similarly, I do the same thing with the prescriber's data. Check and insert if needed. This is the long way, and this is the only way I could figure out how to do it.
I know this is not a very good programming. I'm just an analyst who unfortunately has to do a lot of programming. And I'm learning as I go. With that said, there's a lot of ways to improve this code - I just don't know any. Can you point me to the right direction? Also, an example of how to check and insert the data if it doesn't exist in the database using navigation property. Currently, the data is read and uploaded just fine, but I saw in the database that it didn't quite do what I wanted it to do. It still added a couple of already existing members. I seriously needs some help.