SubSonic 3 Linq Join Problems - linq

using the linqtemplates, I tried getting the linq syntax close to what is in the docs
var query = from c in db.CountyLookups
join s in db.StateLookUps on
c.StateLookupID equals
s.StateLookupID
where c.Name2 == countyName &&
s.Abbr == stateAbbr
select new
{
Latitude = c.Latitude,
Longitude = c.Longitude
};
var result = query.SingleOrDefault();
but when .SingleOrDefault() is called, I get a yellow screen of darn that says:
System.NotSupportedException: The member 'StateLookupID' is not supported
the stack trace ends up at:
SubSonic.Linq.Structure.TSqlFormatter.VisitMemberAccess(MemberExpression m)
the StateLookupID column has underscores in the database and is a regular int pk/fk.
what am I doing wrong?

So apparently VisitMemberAccess has no idea what to do with an int, only string and datetime (starting on line 152 of SubSonic.Linq.Structure.TSqlFormatter). I don't know why this would be called on a join, since a join is usually between an int pk/fk (or guid if you like).
I ended up scrapping the linq query in favor of SubSonic.Query.Select. Here is my new code that works:
var query = db.Select.From<CountyLookup>()
.InnerJoin<StateLookUp>()
.Where(CountyLookupTable.Name2Column)
.IsEqualTo(countyName)
.And(StateLookUpTable.AbbrColumn)
.IsEqualTo(stateAbbr);
I then call ExecuteTypedList and map the results back to my model class. Works like buttah. Just wanted to use linq in this case.

I get this error when I've added properties to my models (the IsValid property as mentioned in ASP.Net MVC 1.0, thanks Rob).
I've had this problem on and off for a bit, and I think I've got it nailed down to the query builder trying to build a query for something that should be done in code, not TSQL.
When it tries to generate the SQL, it descends down the path to generate the TSQL via VisitMemberAccess on a complex type (maybe a another model) but it only knows how to perform operations on datetimes and strings in VisitMemberAccess. I'm sorry if this is a bit incoherent, but I'm trying to get my head around it.
To get around this consider using something like LinqKit AsExpandable prior to any operation which will do the TSQL generation. I've tried this on a simple OrderBy which was going BANG and it appears to work but i have no idea yet what it will do to performance.

Actually I take that back I overcame my problem problem by doing
Stuff.All().Where(x=>x.Someid == id).ToArray()
.AsQueryable()
.Where(x=>x.SomeProp.SomeFlag == true);
It is crud, but it works.

This still appears to be a problem; namely in simple cases such as:
var list = from lang in db.Languages
join site in db.SiteConfigLanguages on
lang.Code equals site.LanguageCode
select lang;
This should evaluate to simple SQL (although pointless in this example):
SELECT Language.* FROM Language LEFT JOIN SiteConfigLanguage ON Language.Code = SiteConfigLanguage.LanguageCode;
It fails inside the same VisitMemberAccess function as (in this case) Language is not a recognisable declaring type (i.e. String or DateTime). It is very similar to the description #matware provided above however it sounds as though the "IsValid" member is pure C# code whereas in this case lang.Code is simply a reference to a column in the database.
I'm currently investigating workarounds as this is only a portion of the larger LINQ query which is failing for me; if I find anything I will post it here. Otherwise, any other solutions/workarounds to this problem known?
UPDATE: Ignore me here; this is simply due to me missing a simple line on the LINQ statement; you need to make sure that you use the "into" keyword to complete things!
i.e.
var list = from lang in db.Languages
join site in db.SiteConfigLanguages on
lang.Code equals site.LanguageCode into sl
from siteLang in sl.DefaultIfEmpty()
select lang;
I've got another error mind you but at least this particular exception is solved. The next one looks a bit nastier unfortunately (inside System.Linq library).

Related

Spring Data JPA fetching list always returns at least a single result

I've noticed a slight problem with how my API is working where I'm using Spring Data JPA.
My query looks something along the lines of:
#Query("SELECT p.id AS id, COUNT(l) AS likes FROM Post p LEFT JOIN Like l ON l.post = p WHERE p.location.id = ?1")
My actual query is bigger, this this contains everything necessary to explain what the issue is. This query will return a list, but assume the location does not exist, it should return null or an empty list, correct? Oh, how wrong you are, my sweet summer child!
This query will instead always return a list of at least one element, regardless of whether or not there are any posts linked to said location.
[{"id": null, "likes": 0}]
That is what the result looks like when serialized to JSON. I am not quite sure what to do about this little predicament, as I obviously don't want to return a list with faulty data, but needing to use processing to filter out duds also seems dumb and unnecessary.
Is there any way to prevent this that I've yet to find? If it is of any relevance, I am using projections currently for my responses.
What I've tried so far:
Adding a not null condition for fields. Does not work, ignored by COUNT.
Adding constraints to all fields #NotNull. Does not work, will still become null.
For what it's worth, I've tried different kinds of joins, though anything but LEFT JOIN doesn't make much sense.
I haven't been able to find any other case which resembles this either, although it most likely exists, but is drowned out by everything else. I'm not quite sure what can be done in this regard, so I'm curious if it's just a quirk with the framework, or if there is an actual solution.
It might be possible to solve through native queries, but I would prefer not to use them.
I'm no SQL expert but I believe that a left join will give you this result if the ID does not exist.
Have you run the query in your DB? Doesn't it give you one row in your result set for IDs that do not exist?
I believe this is intended to say there is a 0 match.
You might want to validate your query before running it. Meaning checking that the location exists first.
As the issue is inherently due to a COUNT and CASE keyword in my real query, resulting in there always being at least one row, and I can't find any method of doing this automatically, the solution I've used is the following:
List<Item> items = repository.customQuery(id);
if (0 < items.size() && null == items.get(0).getId()) {
items.remove(0);
}
The first condition is arbitrary as I know there is always at least one entry, but is done just as a safety measure. A try-catch block would do the trick as well. In the case where you use a primitive int instead of Integer, you'd need to initialize the value in the constructor to something which would normally never be present in the database, such as -1.
If anyone knows of a better method, I'd love to know about it.

SPMETAL / LINQ to SharePoint Decimal Types

I've hit a pretty major snag with the entities generated by spmetal / linq to sharepoint. I am hoping someone has dealt with this before.. or maybe I am missing something obvious.
Let's say we have a list with a number field. The field will be expected to hold reasonably precise values.. for example, 0.0000451. Once the value is in the list- SharePoint is fine with it. It displays in the list and display/edit views correctly.
Now if we generate entities based on this list with spmetal, we will get..
//...
private System.Nullable<double> _number;
//..
[Microsoft.SharePoint.Linq.ColumnAttribute(Name="Number", Storage="_number", Required=true, FieldType="Number")]
public System.Nullable<double> Number {
get {
return this._number;
}
set {
if ((value != this._number))
{
this.OnPropertyChanging("Number", this._number);
this._number= value;
this.OnPropertyChanged("Number");
}
}
}
//...
Since the type determined by spmetal is doublewe get notation when trying to retrieve it.. for example:
var number = (from x in myDc.MyList select x.Number).First();
number would actually result in a double of 4.51E-05, not 0.0000451.
I am assuming this can be fixed by using a decimal. If I change the types throughout the generated entities to System.Nullable<decimal> I get type conversion failures.
How should I fix this?
EDIT I think maybe it is better to ask "how should I deal with this"? for example, I can simply convert my double values to decimal later on down the line.. my linq query, for example. If I do that, the example case would return the expected result. That seems clunky, though, and I'd like to correct this at the source.
There are several cases like this where SPMetal will give you clunky code. You can, and sometimes have to, fix that. And I admit, it definitely feels better to do it at the source.
But there is a downside.
When your data model changes you will have to re-run SPMetal to incorporate your new entities. Any changes you made to the generated file will have to be carefully documented and re-done, or your code will be broken. Therefore, I would advise to leave the generated code alone if you can work with it.
If you can write a wrapper around the objects/methods it would of course be preferable to just converting the types at the end-point, but that's general good programming practice.
4.51E-05 actually equals 0.0000451 so there is nothing wrong with your code.
In other words 4.51E-05 means 4.51 times ten to the minus five power, or 0.0000451

Int equals String in Linq

Basically I have this problem:
var item =
from itemCT in listC
join ditemRef in servRef.Repository.GetQuery(efContext).DefaultIfEmpty()
on itemCT.specialStringID equals ditemRef.refID
into DitemRef
The problem is that itemCT.specialStringID is a string ( didnt design it ... can't change it )
Still I am required to make the join work. Any hints ?
Looking for related answers I've tried using SqlFunctions.StringConvert((double)ditemRef.refID without success.
Any hints towards the light at the end of the tunnel helps
Many methods found in the System.Convert class are supported within a LINQ-to-Entities query. Use it to convert one of the two types to the other. Then you'll be able to write your query.

ORA-00907 Error when using Analytic Function in a Query (PS/Query, Peopletools 8.51.12)

Query's throwing an ORA-00907 Error when I try to paste a list of values into a criteria.
Background: I'm not a developer, I'm just an end user that's studied enough to where I can write queries using PS/Query within Peoplesoft,
for my company's implementation. I work with Peoplesoft's FSCM module
(Financials and Supply Chain Management), currently on Version FSCM
8.90.08.024, using I think Oracle 11g as the base database.
I'm mostly self-taught, and the technical experts we have are busy
with database/application stuff, or they aren't familiar with my
section's specific data needs.
I should point out that I'm unable to directly write SQL statements to
Query the database. I have to use a built-in program called "PS/Query"
(also known as Query Manager) with a GUI that writes the SQL for you
and saves it as a Query that you can run to the database to extract
data. This is relevant to my question only in that:
1. I cannot create or alter views/tables
2. I cannot perform any type of SQL Statement except "SELECT"
3. I can embed PL/SQL, MetaSQL and plain SQL into Expressions
4. At this point, Query Manager is the only option I have.
PS/Query is my only experience with SQL so far, aside from Oracle's
documentation and sites like this. From my research, it's considered
extremely confining by "actual" SQL programmers.The restrictions on it
require you to do things in a manner that violates what seem to be
best practices of SQL coding.
Query Request: I have a query I've been requested to write that pulls out spend (on Vouchers and POs) against certain system-defined
Category Codes. What I'm trying to do is pull in Voucher IDs, sum the
merchandise amounts on them by Vendor and Category Code, and display
the results. Or in other words, for every unique combination of
Vendor/Category, add up all the Voucher Amounts that have that
Vendor/Category combination.
Using the SUM (Fieldname) OVER (PARTITION BY fieldname, fieldname)
syntax.
So the end result should look something like...
Code Vendor Amount
123-45 Acme $5000.00
123-45 Apple $4200.00
123-46 Acme $750.00
With that said, here's the SQL that Query Manager is displaying to get the result set I showed above:
SELECT DISTINCT D.CATEGORY_CD, D.TN_DESCR1000, C.VENDOR_ID, E.NAME1, SUM ( A.MERCH_AMT_VCHR) OVER (PARTITION BY D.CATEGORY_CD, C.VENDOR_ID),E.SETID,E.VENDOR_ID
FROM PS_PO_LINE_MATCHED A, PS_PO_LINE B, PS_PO_HDR C, PS_ITM_CAT_TBL D, PS_VENDOR E, PS_PYMNT_VCHR_XREF F
WHERE A.BUSINESS_UNIT = B.BUSINESS_UNIT
AND A.PO_ID = B.PO_ID
AND A.LINE_NBR = B.LINE_NBR
AND B.BUSINESS_UNIT = C.BUSINESS_UNIT
AND B.PO_ID = C.PO_ID
AND D.CATEGORY_ID = B.CATEGORY_ID
AND D.EFFDT =
(SELECT MAX(D_ED.EFFDT) FROM PS_ITM_CAT_TBL D_ED
WHERE D.SETID = D_ED.SETID
AND D.CATEGORY_TYPE = D_ED.CATEGORY_TYPE
AND D.CATEGORY_CD = D_ED.CATEGORY_CD
AND D.CATEGORY_ID = D_ED.CATEGORY_ID
AND D_ED.EFFDT <= SYSDATE)
AND ( F.SCHEDULED_PAY_DT >= TO_DATE('2010-07-01','YYYY-MM-DD')
AND F.SCHEDULED_PAY_DT <= TO_DATE('2011-06-30','YYYY-MM-DD'))
AND D.CATEGORY_CD LIKE :1
AND E.VENDOR_ID = C.VENDOR_ID
AND A.BUSINESS_UNIT = F.BUSINESS_UNIT
AND A.VOUCHER_ID = F.VOUCHER_ID
ORDER BY 1
Underlying Issue: This works fine, but it can only prompt on one
Category Code at a time. Category Codes are 5 digits, a 3-digit
"Class" followed by a dash and then a 2-digit "subclass. I have a list
of 375 Category Codes I need to get this Query result for.
I've set up a prompt on this version that allows entry of a Wildcard
(So 123-%%), but that's still about a hundred separate runs of the
Query. Query Manager allows use of an "In List" expression type in
Criteria, but it requires you to manually enter each entry in the
list.
I'm trying to set it up to where I can paste a plaintext copy of the
Code list into an Expression, with proper quotes/commas, and have it
evaluate that to give me a combined list of all the NIGP codes
specified. The Prompt field created by Query Manager doesn't allow
pasting of lists (as far as I know).
Attempted Solution: I viewed the page at http://peoplesoft.ittoolbox.com/groups/technical-functional/peoplesoft-other-l/create-an-expression-in-psoft-90-query-to-paste-a-list-of-emplids-2808427 and I've tried some of the answers given there, but none of them worked. That page led to me trying this modified SQL (obviously the list of codes is truncated a bit for display here):
SELECT DISTINCT D.CATEGORY_CD, D.TN_DESCR1000, C.VENDOR_ID, E.NAME1, SUM ( A.MERCH_AMT_VCHR) OVER (PARTITION BY D.CATEGORY_CD, C.VENDOR_ID),E.SETID,E.VENDOR_ID
FROM PS_PO_LINE_MATCHED A, PS_PO_LINE B, PS_PO_HDR C, PS_ITM_CAT_TBL D, PS_VENDOR E, PS_PYMNT_VCHR_XREF F
WHERE A.BUSINESS_UNIT = B.BUSINESS_UNIT
AND A.PO_ID = B.PO_ID
AND A.LINE_NBR = B.LINE_NBR
AND B.BUSINESS_UNIT = C.BUSINESS_UNIT
AND B.PO_ID = C.PO_ID
AND D.CATEGORY_ID = B.CATEGORY_ID
AND D.EFFDT =
(SELECT MAX(D_ED.EFFDT) FROM PS_ITM_CAT_TBL D_ED
WHERE D.SETID = D_ED.SETID
AND D.CATEGORY_TYPE = D_ED.CATEGORY_TYPE
AND D.CATEGORY_CD = D_ED.CATEGORY_CD
AND D.CATEGORY_ID = D_ED.CATEGORY_ID
AND D_ED.EFFDT <= SYSDATE)
AND ( F.SCHEDULED_PAY_DT >= TO_DATE('2010-07-01','YYYY-MM-DD')
AND F.SCHEDULED_PAY_DT <= TO_DATE('2011-06-30','YYYY-MM-DD'))
AND D.CATEGORY_CD = '005-00' OR D.CATEGORY_CD IN ('015-00,'' '015-06,'' '015-10,'' '615-07'')
AND E.VENDOR_ID = C.VENDOR_ID
AND A.BUSINESS_UNIT = F.BUSINESS_UNIT
AND A.VOUCHER_ID = F.VOUCHER_ID
ORDER BY 1
And the SQL above is what's giving me the ORA-00907 error. Has anyone ran into this problem before? Massive wall of text, I know. My apologies. This is my first post here and I'm trying not to leave anything relevant out.
I've got the immediate problem that spurred this question fixed,but that request is just the tip of a very large iceberg, and at some point I need to figure out a way to be able to paste plaintext lists in as criteria using Query Manager, preferably in a way that plays nice with Analytic Grouping.
TL;DR version:
Using Peoplesoft Query Manager to do an Analytic SUM with grouping using OVER, PARTITION BY. When I try to paste a list into the criteria, it throws an ORA-00907 Error.
Any help would be greatly appreciated. Thanks!
Ok, after a bit more tweaking with this, I've found what I think is the underlying issue.
The error, in this case, is two-fold. Part of it was my fault (I didn't check for Peoplesoft mangling the quotation marks I pulled from Word), and part of it was the way Query Manager interprets some kinds of functions (you have to wrap some stuff in a Case When statement to get it to evaluate properly).
First, the "My Fault" part:
Every time I was pasting in my list of test NIGP Codes, I was doing it from a file I kept saved in Microsoft Word.
Which has the probably-handy "replace straight quotes with smart quotes" feature. Peoplesoft goes bonkers when its presented a "smart quote", and will display them as upside-down question marks (there's probably a technical term, I don't know it).
So when I'd test suggestions (such as fixing the quote/comma order as suggested by #Rene Nyffenegger and #WayneH) I'd start with my base test query, add in the expressions and test it, saving it as a separate query. If they didn't work, I'd go back to the base query. That way I could iterate changes and save potential tests as different versions.
My mistake was in not saving the different versions, leaving the application and going back in. It's when you save the query, leave the page, go somewhere else in Peoplesoft, then go back to open Query Manager that it actually shows you that it's doing the character conversion. You can't see it unless you do that. Even though Query Manager is doing it. So it was throwing a character Query Manager wouldn't recognize, but not showing me the character it wouldn't recognize.
I got a new work PC recently, and I've now disabled the Smart Quotes auto-replace for future use.
Second, the "Query Manager: part:
On the version of this that I got to work, I made use of wrapping the "IN" function inside a Case statement. I've found that a lot of SQL functions, when used "plain" (as I'd define them by just copy-pasting from Oracle's definitions pages and filling in the appropriate variables) tend to give PS/Query (Query Manager) heartburn. But if you wrap them inside a CASE...WHEN...END statement that evaluates the result of the function and then build a criteria that selects based on certain values of that result, the function will work and properly display a result.
So for an example, set up this expression (like in the example from #qyb2zm302). I'm using different codes from what was in my original example, but they work the same (they're all five-digit, character-typed codes consisting of three digits, a dash, then two digits)
Case when E.CATEGORY_CD IN
('375-15', '375-30', '375-54', '375-60', '380-30','938-63')
then 'true'
else 'false'
end
And then set a criteria:
AND
Case when E.CATEGORY_CD IN
('375-15', '375-30', '375-54', '375-60', '380-30','938-63')
then 'true'
else 'false'
end
= 'true'
It'll run to completion and return any rows that have that Category Code.
If you don't want to do that, you can do like in #qyb2zm302's Method 2. The only downside to that in Query Manager is that you have to enter them into individual rows in the "List", and if you can only copy-paste 25 at a time.
Wrapping it in a Case Statement lets you paste it directly into an Expression, which is far better for larger lists.
Solutions:
The above is the code I went with that worked. It's simplifying a bit for brevity's sake, but it works.
In List works through the native Query Manager option as long as you manually-populate the list
D.CATEGORY_CD = '005-00' OR works as long as you wrap it in a Case Statement
D.CATEGORY_CD IN ('015-00','015-06','015-10','615-07') works as long as you wrap it in a Case Statement
Peoplesoft hates Smart Quotes. None of the above will work if you're copying quotation marks directly from Word, but you won't see it unless you save, leave and come back to the same query in edit mode
Formatting is important. All of the above require the proper comma/quotation formatting, as pointed out by Rene and Wayne. Meaning: ('xxx-xx', 'xxx-01','xxx-02') etc
Thanks to everyone who helped on this! I don't think I've head-desked this hard before on any question, but I guess that's part of the learning process. Since all the answers posted are valid and correct (or at least a portion of the larger "correct"), I'm going to flag them all.
The
D.CATEGORY_CD IN ('015-00,'' '015-06,'' '015-10,'' '615-07'')
part looks fishy to me
Since a '' within a string "evaluates" to a single ' the first string is
'015-00,'' '
followed by (the non-string)
015-06,
The following '' is probably the thing that the parser stumbles upon since it's pretty meaningless.
Edit try it with a D.CATEGORY_CD IN ('015-00', '015-06', '015-10', '615-07').
Following the link you posted, I see 2 methods for doing what you are trying to accomplish.
I also notice that you tried a 3rd method.
Method 1
Criteria > Add Criteria
Expression Type: Character
Length: 255
Expression Text: D.CATEGORY_CD IN ('015-00','015-06','015-10','615-07') AND 1
Condition Type: equal to
Constant: 1
Method 2
Criteria > Add Criteria
Field: D.CATEGORY_CD
Condition Type: in list
Value: 015-00','015-06','015-10','615-07
Method 3 (Your Method)
Criteria > Add Criteria
Field: D.CATEGORY_CD
Condition Type: equal to
Define Expression: '015-00' OR D.CATEGORY_CD IN ('015-00','015-06','015-10','615-07')
Question) Does the below exactly match the text you are putting the Expression box?
'015-00' OR D.CATEGORY_CD IN ('015-00','015-06','015-10','615-07')
If not, what are you putting in that box?
I think the D.CATEGORY_CD criteria are giving you the problems, I changed the double quotes to single quotes and then it still looked strange to me. I then notice the commas are inside your quotes and not between them, try making the one criteria line look like this:
before:
OR D.CATEGORY_CD IN ('015-00,'' '015-06,'' '015-10,'' '615-07'')
after:
OR D.CATEGORY_CD IN ('015-00', '015-06', '015-10', '615-07')
Also, the "IN" is an implied "OR" and I am not sure if you have parenthesis around the two D.CATEGORY_CD,
I would just put the one additional code into the IN criteria and remove the "D.CATEGORY_CD =" line:
before:
AND D.CATEGORY_CD = '005-00' OR D.CATEGORY_CD IN ('015-00', '015-06', '015-10', '615-07')
after:
AND D.CATEGORY_CD IN ('015-00', '015-06', '015-10', '615-07', '005-00')
Of course, you are already ordering by CATEGORY_CD, you could remove this criteria and pull all categories in one run (that is unless there are too many rows for excel), and then you might also want to include either VENDOR_ID or NAME1 in the ORDER BY clause.
Hope that helps you.

Using Linq to select a list of Entities, linked Entities, linked Entities

Apologies for the poor question title - I'm not sure how to describe what I'm doing but that is the best I could come up with, please edit it if what I'm asking for has a real name!
I have Programmes, which can have a group of Projects assigned, which in turn have groups of Outputs assigned.
I would like to get all the outputs for the Programme through it's projects as one big list of outputs. I have this:
From pp In Me.ProgrammeProjects Select pp.Project.Outputs
Which basically gets me a list of output lists. (An Ienumerable Of EntitySet Of Output).
I'm brute forcing my way through Linq and can't find any examples of this (or can't recognise one when I see it). How can I do this using just Linq rather than for loops and Linq where I'd go through each EntitySet and add it's contents to a bigger list?
Thanks
Or go against the linq context directly:
from o in context.Outputs
where o.Project.ProgrammeProjects.ID = 1
select o
The reverse will work too and query straight from the data context's table.
Are you trying to get a list of outputs for a specific programme?
If so, try something like this:
var result = (from pp in ProgrammeProjects
where pp.Name.Equals("ProjectA")
select pp.Project.Outputs).ToList();
or
once you get your list of outputs, you could use a lambda expression to get a subset.
var result = (from pp in ProgrammeProjects
select pp.Project.Outputs).ToList();
var subResult = result.FindAll(target => target.OutputParameter.Equals("findThisValue");
Is this what you're trying to do?
If not, give a bit more detail of the data structure and what you're trying to retrieve and I'll do my best to help.
Patrick.
This is the way I've resorted to doing it, but I can tell it's going to be slow when the amount of data increases.
Dim allOutputs As New Generic.List(Of Output)
Dim outputLists = From pp In Me.ProgrammeProjects Select pp.Project.Outputs.ToList
For Each outputList In outputLists
Dim os = From o In outputList Where o.OutputTypeID = Type Select o
allOutputs.AddRange(os)
Next
Return allOutputs
I'm still a bit confused as to what kind of data you're trying to retrieve. Here is what I understand.
You have a list of Programmes
Each Programme can have many Projects
Each Project can have many outputs.
Goal: To find all outputs of a certain type. Is this right?
It doesn't look like you're retrieving any data related to the project or programme so
something like this should work:
Dim allOutputs As Generic.List(Of Outputs) = (From output In Me.Outputs Where output.OutputType.Equals(Type) Select output).ToList()
Let me know how it goes.
Patrick.

Resources