I'm pretty new to SSRS, may not be possible, but can I have a WHERE clause written in an expression?
I bassically have a dataset, but only want to assign the value to a text box based on the values in the dataset.
In linq, it'd look like:
ds.FirstOrDefault(x => x.IsHeader) but I can't work out the expression syntax. There is the First function, but that just gives me the first record - not filtered as its applied after the filters.
Anyone have any ideas - otherwise I need to split my dataset into multiple datasets, which is not ideal
Thanks in advance
You can do filtering in the First Expression like so:
=First(Fields!MiddleInitial.Value = "P")
=First(Fields!MiddleInitial.Value = Parameters!MiddleInitial.Value(0))
=First(Fields!MiddleInitial.Value,"AdventureWorks")
So for your example you'd have an expression that looks something like this (assuming your textbox is bound to ds):
=First(Fields!IsHeader.Value = True)
If the textbox isn't bound to ds you should be able to do this:
=First(Fields!IsHeader.Value = True, "ds")
it's best to do filtering in your SQL query.
You can set up a parameter in your dataset to properly display the data you want.
Related
I have a matrix that has a group filtered at the matrix level. I can't filter the SQL because it is very large and is used all over my report.
I need to be able to specify the columns to display after the filter is applied.
The end filter would look something like this
if ColumnA[value] IN Test1,Test2,Test3 OR ColumnB[name]
As you can see I want a value string filter and make sure ColumnB get displayed at all times.
Or being able to specify the columns to show in the matrix would work also.
You can filter at the dataset level: see here for more detail.
To filter a tablix, go into Tablix Properties and open up the Filters tab. You can write a Boolean expression (must evaluate to TRUE for the record to come into the Tablix) to do the filtering there.
I ended up using a tablix and creating columns for each column I wanted to display and rows for each row item. I then used a Count(IIF()) statement to match the specific item I needed to calculate for that cell. I wanted to use the matrix so it would not be so long winded but in the end I got the job done. I have since used this method on many occasions.
I have this here:
Dim query = FromTableRows.Select(Function(Row) Row.Item(_SqlSyntaxChecker.SelectedFields(0)))
Row is a normal DataRow, so I can get the field value of the rows like this: Row.Item(0), Row.Item(1), etc.
SelectedFields contains the field names of the FromTableRows.
Now, I would like to select all the fields in the SelectedFields list, while the number of the selected fields can vary.
Is this possible? How should I modify the code?
Thanks.
You can simply make use of the ItemArray property, if I understand your question correctly.
FromTableRows.Select(Function(Row) Row.ItemArray)
The ItemArray property is an object array that contains the elements found in the DataRow. You will, of course, lose any mapping via this method from columns to elements, but it sounds like that's what you want.
I'm having a problem joining two LINQ queries.
Currently, my (original) code looks like this
s.AnimalTypes.Sort((x, y) => string.Compare(x.Type, y.Type));
What I'm needing to do is change this based on a date, then select all data past that date, so I have
s.AnimalTypes.Select(t=>t.DateChanged > dateIn).ToList()
s.AnimalTypes.Sort((…
This doesn't look right as it's not sorting the data selected, rather sorting everything in s.AnimalTypes.
Is there a way to concatenate the two LINQ lines? I've tried
s.AnimalTypes.Select(t=>t.DateChanged > dateIn).ToList().Sort((…
but this gives me an error on the Sort section.
Is there a simple way to do this? I've looked around and Grouo and OrderBy keep cropping up, but I'm not sure these are what I need here.
Thanks
From your description, I believe you want something like:
var results = s.AnimalTypes.Where(t => t.DateChanged > dateIn).OrderBy(t => t.Type);
You can call ToList() to convert to a List<T> at the end if required.
There are a couple of fundamental concepts I believe you are missing here -
First, unlike List<T>.Sort, the LINQ extension methods don't change the original collections, but rather return a new IEnumerable<T> with the filtered or sorted results. This means you always need to assign something to the return value (hence my var results = above).
Second, Select performs a mapping operation - transforming the data from one form to another. For example, you could use it to extract out the DateChanged (Select(t => t.DateChanged)), but this would give you an enumeration of dates, not the original animal types. In order to filter or restrict the list with a predicate (criteria), you'd use Where instead.
Finally, you can use OrderBy to reorder the resulting enumerable.
You are using Select when you actually want to use Where.
Select is a projection from one a collection of one type into another type - you won't increase or reduce the number of items in a collection using Select, but you can instead select each object's name or some other property.
Where is what you would use to filter a collection based on a boolean predicate.
I have a dropdown(Dimesions) and a stringEdit LookUp(dimensionValue) When I select a dimension suppose 'Branch' and a Value e.g. 'B001' I filter the result with the following query
queryRun.query().dataSourceTable(tablenum(LedgerTrans)).addange(fieldId2Ext(fieldNum(LedgerTrans, Dimensions), dimensions)).value(dimensionValue);
where dimensions is enumValue, in the above query the enumValue for branch is 3 and dimensionValue is a string EDT.
Now I want to filter with multiple dimensionValues e.g. 'B001, B002, B002' etc. What modifications do I have to make in the query? Kindly assist.
With this code you should be able to simply enter "B001, B002, B002" (without the quotes) in your Value StringEdit control.
By the way I would advise you to modify your code as follows so that same ranges wouldn't be added over and over again:
SysQuery::findOrCreateRange(queryRun.query().dataSourceTable(tablenum(LedgerTrans)), fieldId2Ext(fieldNum(LedgerTrans, Dimensions), dimensions)).value(dimensionValue);
I'm tasked with adding an option to our search, which will return results where a given field doesn't begin with a letter of the alphabet. (The .StartsWith(letter) part wasn't so hard).
But I'm rather unsure about how to get the results that don't fall within the A-Z set, and equally hoping it generates some moderately efficient SQL underneath.
Any help appreciated - thanks.
In C# use the following construct, assuming db as a data context:
var query = from row in db.SomeTable
where !System.Data.Linq.SqlClient.SqlMethods.Like(row.SomeField, "[A-Z]%")
select row;
This is only supported in LINQ to SQL queries. All rules of the T-SQL LIKE operator apply.
You could also use less effective solution:
var query = from row in db.SomeTable
where row.SomeField[0] < 'A' || row.SomeField[0] > 'Z'
select row;
This gets translated into SUBSTRING, CAST, and UNICODE constructs.
Finally, you could use VB, where there appears to be a native support for the Like method.
Though SQL provides the ability to check a range of characters in a LIKE statement using bracket notation ([a-f]% for example), I haven't seen a linq to sql construct that supports this directly.
A couple thoughts:
First, if the result set is relatively small, you could do a .ToList() and filter in memory after the fact.
Alternatively, if you have the ability to change the data model, you could set up additional fields or tables to help index the data and improve the search.
--EDIT--
Made changes per Ruslan's comment below.
Well, I have no idea if this will work because I have never tried it and don't have a compiler nearby to try it, but the first thing I would try is
var query = from x in db.SomeTable
where x.SomeField != null &&
x.SomeField.Length >= 1 &&
x.SomeField.Substring(0, 1).All(c => !Char.IsLetter(c))
select x;
The possiblility exists that LINQ to SQL fails to convert this to SQL.