I am trying to fetch a number of records from a sqlite3 database and load them into an array. The code I have written, which seems to function correctly at least as far as retrieving the correct number of records with the right values from the db is
while(results?.next() == true) {
println("Got a result")
var sname = results?.stringForColumn("surname")
var fname = results?.stringForColumn("firstname")
println("Retrieved \(sname) ,\(fname)")
}
The problem I have is that when I try to access the variables in the println statement what it yields is
Retrieved Optional("Smiles") ,Optional("Dick")
I have seemingly tried everything to get just the values but keep getting the Optional(" ") added. Any ideas?
Try this approach:
println("Retrieved \(sname!) ,\(fname!)")
Related
Below is the code written by my collegue who doesnt work in the firm anymore. I am inserting records in object with data loader and I can see success message but I do not see any records in my object. I am not able to understand what below trigger is doing.Please someone help me understand as I am new to salesforce.
trigger DataLoggingTrigger on QMBDataLogging__c (after insert) {
Map<string,Schema.RecordTypeInfo> recordTypeInfo = Schema.SObjectType.QMB_Initial_Letter__c.getRecordTypeInfosByName();
List<QMBDataLogging__c> logList = (List<QMBDataLogging__c>)Trigger.new;
List<Sobject> sobjList = (List<Sobject>)Type.forName('List<'+'QMB_Initial_Letter__c'+'>').newInstance();
Map<string, QMBLetteTypeToVfPage__c> QMBLetteTypeToVfPage = QMBLetteTypeToVfPage__c.getAll();
Map<String,QMBLetteTypeToVfPage__c> mapofLetterTypeRec = new Map<String,QMBLetteTypeToVfPage__c>();
set<Id>processdIds = new set<Id>();
for(string key : QMBLetteTypeToVfPage.keyset())
{
if(!mapofLetterTypeRec.containsKey(key)) mapofLetterTypeRec.put(QMBLetteTypeToVfPage.get(Key).Letter_Type__c, QMBLetteTypeToVfPage.get(Key));
}
for(QMBDataLogging__c log : logList)
{
Sobject logRecord = (sobject)log;
Sobject QMBLetterRecord = new QMB_Initial_Letter__c();
if(mapofLetterTypeRec.containskey(log.Field1__c))
{
string recordTypeId = recordTypeInfo.get(mapofLetterTypeRec.get(log.Field1__c).RecordType__c).isAvailable() ? recordTypeInfo.get(mapofLetterTypeRec.get(log.Field1__c).RecordType__c).getRecordTypeId() : recordTypeInfo.get('Master').getRecordTypeId();
string fieldApiNames = mapofLetterTypeRec.containskey(log.Field1__c) ? mapofLetterTypeRec.get(log.Field1__c).FieldAPINames__c : '';
//QMBLetterRecord.put('Letter_Type__c',log.Name);
QMBLetterRecord.put('RecordTypeId',tgh);
processdIds.add(log.Id);
if(string.isNotBlank(fieldApiNames) && fieldApiNames.contains(','))
{
Integer i = 1;
for(string fieldApiName : fieldApiNames.split(','))
{
string logFieldApiName = 'Field'+i+'__c';
fieldApiName = fieldApiName.trim();
system.debug('fieldApiName=='+fieldApiName);
Schema.DisplayType fielddataType = getFieldType('QMB_Initial_Letter__c',fieldApiName);
if(fielddataType == Schema.DisplayType.Date)
{
Date dateValue = Date.parse(string.valueof(logRecord.get(logFieldApiName)));
QMBLetterRecord.put(fieldApiName,dateValue);
}
else if(fielddataType == Schema.DisplayType.DOUBLE)
{
string value = (string)logRecord.get(logFieldApiName);
Double dec = Double.valueOf(value.replace(',',''));
QMBLetterRecord.put(fieldApiName,dec);
}
else if(fielddataType == Schema.DisplayType.CURRENCY)
{
Decimal decimalValue = Decimal.valueOf((string)logRecord.get(logFieldApiName));
QMBLetterRecord.put(fieldApiName,decimalValue);
}
else if(fielddataType == Schema.DisplayType.INTEGER)
{
string value = (string)logRecord.get(logFieldApiName);
Integer integerValue = Integer.valueOf(value.replace(',',''));
QMBLetterRecord.put(fieldApiName,integerValue);
}
else if(fielddataType == Schema.DisplayType.DATETIME)
{
DateTime dateTimeValue = DateTime.valueOf(logRecord.get(logFieldApiName));
QMBLetterRecord.put(fieldApiName,dateTimeValue);
}
else
{
QMBLetterRecord.put(fieldApiName,logRecord.get(logFieldApiName));
}
i++;
}
}
}
sobjList.add(QMBLetterRecord);
}
if(!sobjList.isEmpty())
{
insert sobjList;
if(!processdIds.isEmpty()) DeleteDoAsLoggingRecords.deleteTheProcessRecords(processdIds);
}
Public static Schema.DisplayType getFieldType(string objectName,string fieldName)
{
SObjectType r = ((SObject)(Type.forName('Schema.'+objectName).newInstance())).getSObjectType();
DescribeSObjectResult d = r.getDescribe();
return(d.fields.getMap().get(fieldName).getDescribe().getType());
}
}
You might be looking in the wrong place. Check if there's an unit test written for this thing (there should be one, especially if it's deployed to production), it should help you understand how it's supposed to be used.
You're inserting records of QMBDataLogging__c but then it seems they're immediately deleted in DeleteDoAsLoggingRecords.deleteTheProcessRecords(processdIds). Whether whatever this thing was supposed to do succeeds or not.
This seems to be some poor man's CSV parser or generic "upload anything"... that takes data stored in QMBDataLogging__c and creates QMB_Initial_Letter__c out of it.
QMBLetteTypeToVfPage__c.getAll() suggests you could go to Setup -> Custom Settings, try to find this thing and examine. Maybe it has some values in production but in your sandbox it's empty and that's why essentially nothing works? Or maybe some values that are there are outdated?
There's some comparison if what you upload into Field1__c can be matched to what's in that custom setting. I guess you load some kind of subtype of your QMB_Initial_Letter__c in there. Record Type name and list of fields to read from your log record is also fetched from custom setting based on that match.
Then this thing takes what you pasted, looks at the list of fields in from the custom setting and parses it.
Let's say the custom setting contains something like
Name = XYZ, FieldAPINames__c = 'Name,SomePicklist__c,SomeDate__c,IsActive__c'
This thing will look at first record you inserted, let's say you have the CSV like that
Field1__c,Field2__c,Field3__c,Field4__c
XYZ,Closed,2022-09-15,true
This thing will try to parse and map it so eventually you create record that a "normal" apex code would express as
new QMB_Initial_Letter__c(
Name = 'XYZ',
SomePicklist__c = 'Closed',
SomeDate__c = Date.parse('2022-09-15'),
IsActive__c = true
);
It's pretty fragile, as you probably already know. And because parsing CSV is an art - I expect it to absolutely crash and burn when text with commas in it shows up (some text,"text, with commas in it, should be quoted",more text).
In theory admin can change mapping in setup - but then they'd need to add new field anyway to the loaded file. Overcomplicated. I guess somebody did it to solve issue with Record Type Ids - but there are better ways to achieve that and still have normal CSV file with normal columns and strong type matching, not just chucking everything in as strings.
In theory this lets you have "jagged" csv files (row 1 having 5 fields, row 2 having different record type and 17 fields? no problem)
Your call whether it's salvageable or you'd rather ditch it and try normal loading of QMB_Initial_Letter__c records. (get back to your business people and ask for requirements?) If you do have variable number of columns at source - you'd need to standardise it or group the data so only 1 "type" of records (well, whatever's in that "Field1__c") goes into each file.
The following code is giving the above error, and I cannot figure out why:
var x = _sqlConn.Connection().QueryResults<Results>("MyDb.dbo.get_records", new { id = theId });
int retVal = x.Outputs.Return_Value;
if (retVal == 0) // ...meaning result set was also returned...fine to this point.
{
var list = x.Outputs.Set1; // exception thrown here with above error
var temp = list.FirstOrDefault();
I have been using other features of Insight.Database for a number of years, but have not had to retrieve a SQL RETURN value at the same time as a recordset. The SQL itself works correctly in SSMS, returning a result set and the RETURN value of 0, as expected. This is happening in VS2019, .NET 4 and .NET 4.5.2; Insight.Database 5.2.7 and 5.2.8.
I got this code from the following page:
https://github.com/jonwagner/Insight.Database/wiki/Specifying-Result-Structures
where it shows this:
var results = connection.QueryResults<Beer, Glass>("GetAllBeersAndAllGlasses");
IList<Beer> beers = results.Set1;
which I combined with the following code from here:
https://github.com/jonwagner/Insight.Database/wiki/Output-Parameters
var results = connection.QueryResults<Results>("MyProc", inputParameters);
var p = results.Outputs.p;
That part works. It's accessing .Set1 that is failing, and I am not sure how to track down why.
I do not have experience with the FastExpando class, but Jon promised magic, and I want to believe. Thanks for any help.
I haven’t tried results+dynamic objects in a while…
I think it is because you are doing:
QueryResults<Results> and Results is an Insight type
You probably want:
QueryResults<MyType>
And then you get back a Results<MyType>
Which contains the return val and Set1
If not, post a ticket over on github and we will help you out.
I want to split the values selected from couch db in gwt according to a particular id. I tried to use the String tokenizer but couldn't found something useful. the result returned from couch db is in the following format:
{"_id":"2","_rev":"1-717f76046030a683687ace9ac8f7bdbf","course":"jbdgjbj","passwd":"rty","phone":"24125514444","clgnme":"bjfbjf","address":"jbjfbjb","name":"meenal","cpasswd":"rty","user":"2","fname":"jfbg"}
I just want to get the values and set them in textboxes.
how to do it?
try this ...
Session studentDbSession = new Session("localhost",5984);
Database studentCouchDb = studentDbSession.getDatabase("student");
System.out.println("select");
Document d = studentCouchDb.getDocument(input);
if(d.containsKey("FirstName")){
fname=d.getString("FirstName");//fname is variable
}
if(d.containsKey("LastName")){
lname=d.getString("LastName");//lname is variable
}
if(d.containsKey("Address")){
add= d.getString("Address");//add name is variable
}
finally concatenate all strings and return to client...
all=fname+" "+lname+" "+add;
return all;
This looks like JSON. You can parse it using JSONObject:
JSONObject obj = new JSONObject(yourString);
String course = obj.getString("course");
This seems like it should be so easy, but I've tried three or four ways to do it (but to no avail).
I'm just trying to put a query result in a viewbag and display it.
I've tried putting a model object list in a ViewBag:
var mesg = from MSG in lemondb.Messages
where MSG.msg == Membership.GetUser().ToString()
select MSG;
ViewBag.messages = MSG;
And then I try to spit it out in a .cshtml:
var message = (List<LemonTrader.Models.Message>)ViewBag.messages; // <--- fails here because it is a string
foreach ( var MSG in message )
{
#Html.Label(MSG.msg)<br />
}
But it says:
Cannot convert type
'System.Data.Entity.Infrastructure.DbQuery'
to
'System.Collections.Generic.List'
So it seems I'm using using the wrong template. How do I spit out a System.Entity.Infrastructure.DbQuery?
I've also tried passing the results through the Viewbag as a list of strings. (Is that a worse way to do it?)
var mesg = from MSG in lemondb.Messages
where MSG.msg == Membership.GetUser().ToString()
select MSG.msg;
ViewBag.messages = mesg;
And spitting it out as a string list:
foreach (var atext in ViewBag.messages as List<string>) { // gets hung up on foreach here (why???)
#Html.Label( atext )
}
And I get this:
Object reference not set to an
instance of an object.
And it points at the "foreach" keyword.
Does that mean there were no messages? Or what?
I wish there was a tutorial showing how to put queryresults in a ViewBag and how to get them out! I've seen tutorials that return an object.ToList() without respect to any kind of "where" mechanism, but no examples to pull out a few, relevant entries and display them.
Try
ViewBag.messages = MSG.ToList();
Also, System.Data.Entity.Infrastructure.DbQuery implements IEnumerable ( http://msdn.microsoft.com/en-us/library/system.data.entity.infrastructure.dbquery(v=vs.103).aspx ) so this should also work:
var message = (IEnumerable<LemonTrader.Models.Message>)ViewBag.messages;
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What is the best way to check if an object exists in the database from a performance point of view? I'm using Entity Framework 1.0 (ASP.NET 3.5 SP1).
If you don't want to execute SQL directly, the best way is to use Any(). This is because Any() will return as soon as it finds a match. Another option is Count(), but this might need to check every row before returning.
Here's an example of how to use it:
if (context.MyEntity.Any(o => o.Id == idToMatch))
{
// Match!
}
And in vb.net
If context.MyEntity.Any(function(o) o.Id = idToMatch) Then
' Match!
End If
From a performance point of view, I guess that a direct SQL query using the EXISTS command would be appropriate. See here for how to execute SQL directly in Entity Framework: http://blogs.microsoft.co.il/blogs/gilf/archive/2009/11/25/execute-t-sql-statements-in-entity-framework-4.aspx
I had to manage a scenario where the percentage of duplicates being provided in the new data records was very high, and so many thousands of database calls were being made to check for duplicates (so the CPU sent a lot of time at 100%). In the end I decided to keep the last 100,000 records cached in memory. This way I could check for duplicates against the cached records which was extremely fast when compared to a LINQ query against the SQL database, and then write any genuinely new records to the database (as well as add them to the data cache, which I also sorted and trimmed to keep its length manageable).
Note that the raw data was a CSV file that contained many individual records that had to be parsed. The records in each consecutive file (which came at a rate of about 1 every 5 minutes) overlapped considerably, hence the high percentage of duplicates.
In short, if you have timestamped raw data coming in, pretty much in order, then using a memory cache might help with the record duplication check.
I know this is a very old thread but just incase someone like myself needs this solution but in VB.NET here's what I used base on the answers above.
Private Function ValidateUniquePayroll(PropertyToCheck As String) As Boolean
// Return true if Username is Unique
Dim rtnValue = False
Dim context = New CPMModel.CPMEntities
If (context.Employees.Any()) Then ' Check if there are "any" records in the Employee table
Dim employee = From c In context.Employees Select c.PayrollNumber ' Select just the PayrollNumber column to work with
For Each item As Object In employee ' Loop through each employee in the Employees entity
If (item = PropertyToCheck) Then ' Check if PayrollNumber in current row matches PropertyToCheck
// Found a match, throw exception and return False
rtnValue = False
Exit For
Else
// No matches, return True (Unique)
rtnValue = True
End If
Next
Else
// The is currently no employees in the person entity so return True (Unqiue)
rtnValue = True
End If
Return rtnValue
End Function
I had some trouble with this - my EntityKey consists of three properties (PK with 3 columns) and I didn't want to check each of the columns because that would be ugly.
I thought about a solution that works all time with all entities.
Another reason for this is I don't like to catch UpdateExceptions every time.
A little bit of Reflection is needed to get the values of the key properties.
The code is implemented as an extension to simplify the usage as:
context.EntityExists<MyEntityType>(item);
Have a look:
public static bool EntityExists<T>(this ObjectContext context, T entity)
where T : EntityObject
{
object value;
var entityKeyValues = new List<KeyValuePair<string, object>>();
var objectSet = context.CreateObjectSet<T>().EntitySet;
foreach (var member in objectSet.ElementType.KeyMembers)
{
var info = entity.GetType().GetProperty(member.Name);
var tempValue = info.GetValue(entity, null);
var pair = new KeyValuePair<string, object>(member.Name, tempValue);
entityKeyValues.Add(pair);
}
var key = new EntityKey(objectSet.EntityContainer.Name + "." + objectSet.Name, entityKeyValues);
if (context.TryGetObjectByKey(key, out value))
{
return value != null;
}
return false;
}
I just check if object is null , it works 100% for me
try
{
var ID = Convert.ToInt32(Request.Params["ID"]);
var Cert = (from cert in db.TblCompCertUploads where cert.CertID == ID select cert).FirstOrDefault();
if (Cert != null)
{
db.TblCompCertUploads.DeleteObject(Cert);
db.SaveChanges();
ViewBag.Msg = "Deleted Successfully";
}
else
{
ViewBag.Msg = "Not Found !!";
}
}
catch
{
ViewBag.Msg = "Something Went wrong";
}
Why not do it?
var result= ctx.table.Where(x => x.UserName == "Value").FirstOrDefault();
if(result?.field == value)
{
// Match!
}
Best way to do it
Regardless of what your object is and for what table in the database the only thing you need to have is the primary key in the object.
C# Code
var dbValue = EntityObject.Entry(obj).GetDatabaseValues();
if (dbValue == null)
{
Don't exist
}
VB.NET Code
Dim dbValue = EntityObject.Entry(obj).GetDatabaseValues()
If dbValue Is Nothing Then
Don't exist
End If