I created a composite primary key column family in cassandra
CREATE TABLE rMessage ( Key varchar,msg_id varchar, msg blob, PRIMARY KEY(key,msg_id) );
I am trying to create a record via Fluent cassandra api.
string key = "cat1";
string id = "2";
CompositeType compositeKey = new CompositeType<FluentCassandra.Types.AsciiType, FluentCassandra.Types.AsciiType>(key,id);
FluentColumnFamily record = ColumnFamily.CreateRecord(compositeKey.ToString());
dynamic r = record.AsDynamic();
r.msg = blob;
record.Columns[0].ColumnTimeUntilDeleted = diff;
Context.Attach(record);
Context.SaveChanges();
The above code return error "Not enough bytes to read value of component 0". I couldn't figure out why.
I tried the below approach but still getting the same error "Not enough bytes to read value of component 0".
var blob = CassandraBinaryFormatter.Serialzie(value);
var compositeKey = new CompositeType<FluentCassandra.Types.UTF8Type, FluentCassandra.Types.UTF8Type>(key, value.ID.ToString());
FluentColumnFamily record = ColumnFamily.CreateRecord(key);
record[compositeKey.ToString()] = blob;
Context.Attach(record);
Context.SaveChanges();
Thanks for help.
Related
I have created store procedure in Sql server its working.when i imliment it into my entity framework, its throws exception, I am new to this, kindly suggest
//SQL//
create procedure sp_getUserID
#deviceID int,
#userID int out
as
Begin
Select #userID= userId from UserTable
where deviceID = #deviceID
End
// C#
var UserID =0;
// This line error ERROR: //The specified parameter name '#userID' is not valid.
System.Data.Entity.Core.Objects.ObjectParameter UserOutput = new System.Data.Entity.Core.Objects.ObjectParameter("#userID", typeof(int));
var objStoredProcd = dbContext.sp_getUserID(UserOutput, UserLogin.DeviceUUID);
UserID = Convert.ToInt32(UserOutput.Value);
I'm trying to call a stored procedure from EntityFramework which uses Table-value parameter.
But when I try to do function import I keep getting a warning message saying -
The function 'InsertPerson' has a parameter 'InsertPerson_TVP' at
parameter index 0 that has a data type 'table type' which is currently
not supported for the target .NET Framework version. The function was
excluded.
I did a initial search here and found few posts which says It's possible in EntityFrameWork with some work arounds and few saying it's not supported in current versions.
Does any one know a better approach or solution for this problem?
I ended up doing this, Please note we are working on EF DataContext(not ObjectContext)
Executing a Stored procedure with output parameter
using (DataContext context = new DataContext())
{
////Create table value parameter
DataTable dt = new DataTable();
dt.Columns.Add("Displayname");
dt.Columns.Add("FirstName");
dt.Columns.Add("LastName");
dt.Columns.Add("TimeStamp");
DataRow dr = dt.NewRow();
dr["Displayname"] = "DisplayName";
dr["FirstName"] = "FirstName";
dr["LastName"] ="LastName";
dr["TimeStamp"] = "TimeStamp";
dt.Rows.Add(dr);
////Use DbType.Structured for TVP
var userdetails = new SqlParameter("UserDetails", SqlDbType.Structured);
userdetails.Value = dt;
userdetails.TypeName = "UserType";
////Parameter for SP output
var result = new SqlParameter("ResultList", SqlDbType.NVarChar, 4000);
result.Direction = ParameterDirection.Output;
context.Database.ExecuteSqlCommand("EXEC UserImport #UserDetails, #ResultList OUTPUT", userdetails, result);
return result == null ? string.Empty : result.Value.ToString();
}
My Table-Value-Parameter (UDT Table) script looks like this:
CREATE TYPE [dbo].[UserType] AS TABLE (
[DisplayName] NVARCHAR (256) NULL,
[FirstName] NVARCHAR (256) NULL,
[LastName] NVARCHAR (256) NULL,
[TimeStamp] DATETIME NULL
)
And my store procedure begins like
CREATE PROCEDURE UserImport
-- Add the parameters for the stored procedure here
#UserDetails UserType Readonly,
#ResultList NVARCHAR(MAX) output
AS
For Stored procedure without output parameter we don't need any ouput parameter added/passed to SP.
Hope it helps some one.
Perhaps we could also consider the SqlQuery method:
[Invoke]
public SomeResultType GetResult(List<int> someIdList)
{
var idTbl = new DataTable();
idTbl.Columns.Add("Some_ID");
someIdList.ForEach(id => idTbl.Rows.Add(id));
var idParam = new SqlParamter("SomeParamName", SqlDbType.Structured);
idParam.TypeName = "SomeTBVType";
idParam.Value = idTbl;
// Return type will be IEnumerable<T>
var result = DbContext.Database.SqlQuery<SomeResultType>("EXEC SomeSPName, #SomeParamName", idParam);
// We can enumerate the result...
var enu = result.GetEnumerator();
if (!enu.MoveNext()) return null;
return enu.Current;
}
var detailTbl = new DataTable();
detailTbl.Columns.Add("DetailID");
detailTbl.Columns.Add("Qty");
txnDetails.ForEach(detail => detailTbl.Rows.Add(detail.DetailID, detail.Qty));
var userIdParam = new System.Data.SqlClient.SqlParameter("#UserID", SqlDbType.Int);
userIdParam.Value = 1;
var detailParam = new System.Data.SqlClient.SqlParameter("#Details", SqlDbType.Structured);
detailParam.TypeName = "DetailUpdate";
detailParam.Value = detailTbl;
var txnTypeParam = new System.Data.SqlClient.SqlParameter("#TransactionType", SqlDbType.VarChar);
txnTypeParam.Value = txnType;
var result = await db.Database.ExecuteSqlCommandAsync("MySP #UserID, #Details, #TransactionType", userIdParam, detailParam, txnTypeParam);
if(result >= 0)
return StatusCode(HttpStatusCode.OK);
else
return StatusCode(HttpStatusCode.InternalServerError);
I've been using JPA to insert entities into a database but I've run up against a problem where I need to do an insert and get the primary key of the record last inserted.
Using PostgreSQL I would use an INSERT RETURNING statement which would return the record id, but with an entity manager doing all this, the only way I know is to use SELECT CURRVAL.
So the problem becomes, I have several data sources sending data into a message driven bean (usually 10-100 messages at once from each source) via OpenMQ and inside this MDB I persists this to PostgreSQL via the entity manager. It's at this point I think there will be a "race condition like" effect of having so many inserts that I won't necessarily get the last record id using SELECT CURRVAL.
My MDB persists 3 entity beans via an entity manager like below.
Any help on how to better do this much appreciated.
public void onMessage(Message msg) {
Integer agPK = 0;
Integer scanPK = 0;
Integer lookPK = 0;
Iterator iter = null;
List<Ag> agKeys = null;
List<Scan> scanKeys = null;
try {
iag = (IAgBean) (new InitialContext()).lookup(
"java:comp/env/ejb/AgBean");
TextMessage tmsg = (TextMessage) msg;
// insert this into table only if doesn't exists
Ag ag = new Ag(msg.getStringProperty("name"));
agKeys = (List) (iag.getPKs(ag));
iter = agKeys.iterator();
if (iter.hasNext()) {
agPK = ((Ag) iter.next()).getId();
}
else {
// no PK found so not in dbase, insert new
iag.addAg(ag);
agKeys = (List) (iag.getPKs(ag));
iter = agKeys.iterator();
if (iter.hasNext()) {
agPK = ((Ag) iter.next()).getId();
}
}
// insert this into table always
iscan = (IScanBean) (new InitialContext()).lookup(
"java:comp/env/ejb/ScanBean");
Scan scan = new Scan();
scan.setName(msg.getStringProperty("name"));
scan.setCode(msg.getIntProperty("code"));
iscan.addScan(scan);
scanKeys = (List) iscan.getPKs(scan);
iter = scanKeys.iterator();
if (iter.hasNext()) {
scanPK = ((Scan) iter.next()).getId();
}
// insert into this table the two primary keys above
ilook = (ILookBean) (new InitialContext()).lookup(
"java:comp/env/ejb/LookBean");
Look look = new Look();
if (agPK.intValue() != 0 && scanPK.intValue() != 0) {
look.setAgId(agPK);
look.setScanId(scanPK);
ilook.addLook(look);
}
// ...
The JPA spec requires that after persist, the entity be populated with a valid ID if an ID generation strategy is being used. You don't have to do anything.
currently I'm Inserting like:
MyNamedEntities db = new MyNamedEntities();
MyTableEntity field = new MyTableEntity();
field.Name = "me";
db.MyTableEntity.AddObject(field);
db.SaveChanges()
But now I want to insert child elements and I need that field.Id part
MyOtherTableEntity field = new MyOtherTableEntity();
field.TableId = new MyTableEntity.First(x => x.Id.Equals( ... ));
How can I get the field.Id ?
If your table has defined the Id as an INT IDENTITY column, then you don't really have to do anything at all! :-)
In that case, just insert your entity and after the call to .SaveChanges(), your object should contain the new Id value:
MyTableEntity field = new MyTableEntity();
field.Name = "me";
db.MyTableEntity.AddObject(field);
db.SaveChanges();
int newID = field.Id;
You can also just add them to the parent by the association before or after the save changes
Something like this.
address a = new address();
a.city = "Detroit";
field.address.add(a);
db.SaveChanges();
I am using the ADO entity framework for the first time and am not sure of the best way of inserting db recored that contain foreign keys.
this is the code that i am using, I would appreciate any comments and suggestion on this.
using (KnowledgeShareEntities entities = new KnowledgeShareEntities())
{
Questions question = new Questions();
question.que_title = questionTitle;
question.que_question_text = questionText;
question.que_number_of_views = 0;
question.que_is_anonymous = isAnonymous;
question.que_last_activity_datetime = DateTime.Now;
question.que_timestamp = DateTime.Now;
question.CategoriesReference.Value = Categories.CreateCategories(categoryId);
question.UsersReference.Value = Users.CreateUsers(userId);
entities.AddToQuestions(question);
entities.SaveChanges();
return question.que_id;
}
You should use something like
question.UsersReference.EntityKey = new EntityKey("MyEntities.Users",
"ID", userId);
You don't have to have User object to set up foreign key, just use ID.