I have a VB .net application in which I want to check if a collection of routes have the same startLocation and destinationLocation, so basically a check for duplicate routes.
I have found a solution for checking exactly the same route:
Dim duplicateLines = Routes.Values.GroupBy(Function(v) New With {Key startLocation, Key destinationLocation}) _
.Where(Function(grp) grp.Count > 1).ToHashSet
But I would also like to check for reversed routes i.e., the start of route 1 is the destination of route 2 and vice versa.
Is this possible with a similar, fast solution (e.g. with LINQ and lambda expressions)?
Thanks!
Related
I am trying to use AWS Config Advanced Query to generate a report against a specific rule I have created.
SELECT
configuration.targetResourceId,
configuration.targetResourceType,
configuration.complianceType,
configuration.configRuleList
WHERE
configuration.configRuleList.configRuleName = 'aws_config-requiredtags-rule'
AND configuration.complianceType = 'NON_COMPLIANT'
Results look similar to this:
[
0:{
"configRuleName":"aws_configrequiredtags-rule"
"configRuleArn":"arn:aws:config:us-east-2:123456789:config-rule/config-rule-dl6gsy"
"configRuleId":"config-rule-dl6gsy"
"complianceType":"COMPLIANT"
}
1:{
"configRuleName":"eaws_config-instanceinvpc-rule"
"configRuleArn":"arn:aws:config:us-east-2:123456789:config-rule/config-rule-dc4f1x"
"configRuleId":"config-rule-dc4f1x"
"complianceType":"NON-COMPLIANT"
}
While this query produces results, it separates my config rule and compliance type, so I am not only getting results where my config rule is ONLY Non-compliance for 'aws_config-requiredtags-rule' results.
I am pretty novice with SQL, but hope there is a way for me to specify that I only want to see Non-Compliant results against a specific rule.
thanks,
This is a limitation of the AWS Config Service - and a pretty big one IMO. When you filter on properties within arrays, those filters are treated like OR operations instead of AND. There doesn't seem to be a good way of performing meaningful queries for individual rules.
From the docs:
When querying against multiple properties within an array of objects, matches are computed against all the array elements
...
The first condition configuration.configRuleList.complianceType = 'non_compliant' is applied to ALL elements in R.configRuleList, because R has a rule (rule B) with complianceType = ‘non_compliant’, the condition is evaluated as true. The second condition configuration.configRuleList.configRuleName is applied to ALL elements in R.configRuleList, because R has a rule (rule A) with configRuleName = ‘A’, the condition is evaluated as true. As both conditions are true, R will be returned.
Looks like a silly question, but I can't find a way to access the DataViews in my DataViewManager.
I can see it in the DataViewManager Visualizer window, so there must be a way.
What am I doing wrong?
dvm = New DataViewManager(MyDS) ''-- MyDS is a strongly typed dataset
dvm.CreateDataView(MyDS.Company)
dvm.CreateDataView(MyDS.Sites)
MsgBox(dvm.DataViewSettings.Count) ''-- shows 7, even though I added only 2.
For Each view As DataView In dvm ''-- Error!
MsgBox(view.Table.TableName)
Next
I also observed that irrespective of how many DataViews I create, data the DataViewManager Visualizer shows all DataViews in my dataset. Why?
how do I hide those rows in parent whose child data view returns 0 rows after applying RowFilter on child
I've done it like this, but it feels like a nasty hack; I've never read the source deeply enough to know if there is a better way:
Add a column to your child datatable: Name: IsShowing, Type: Int, Expression: 1, ReadOnly: True
Put the following code:
ChildBindingSource.RemoveFilter()
ParentBindingSource.RemoveFilter()
YourDataSet.ChildDataTable.IsShowingColumn.Expression = ""
YourDataSet.ChildDataTable.Expression = $"IIF([SomeColumn] Like '{SomeFilterText}',1,0)"
ChildBindingSource.Filter = "[IsShowing] > 0"
ParentBindingSource.Filter = "Sum(Child.IsShowing) > 0"
The removal and re-add triggers a re-evaluation of the expression and the filters. There is probably a way to do this without removing/re-adding but I haven't yet found it.. Expressions are normally only re-evaluated when row data changes; changing an expression doesn't seem to recalculate all the row values/trigger a refresh of the relations and BS filters
It would be great if the parent filter supported complex expressions like SUM(IIF(Child.SomeColumn = 'SomeFilter',1,0)>0 but the SUM operator expects only a column name in the parent or child. As such, the circuitous route of having a column with an Expression be the part inside the SUM is the only way i've found to leverage the built in filtering
Remember when you test that the search is case sensitive. If you want it not to be you might have to have another column of data that is the lowercase version of what you want to search and lowercase your query string
Having a bit of trouble having not long started with Entity Framework.
I have two tables which have a 0 to 1 relationship. When I select a row from the main table (staff) it's fine unless I select a row that has no joining record in the second table (status). If I do this, then it throws up 'Object reference not set to instance of an object' when it's trying to access the proprty of the second table:
If Not cls.STATUS_DESC.STAFF_INFO Is DBNull.Value Then
lblStatusDescription.Text = cls.STATUS_DESC.STAFF_INFO
End If
The LINQ I use to get the record is:
Dim account As STAFF =
(From a In sa.STAFFs
Where a.STAFF_NO = staffno
Select a).FirstOrDefault
There is no direct reference to the sub table in the statement, however the join is defined in the database diagram which allows me to reference the properties.
I'm certain it's a very basic issue, but like I said I've only just started using it!
I'm not sure if I can interpret your code correctly but I think it has to do with the Lazy Loading feature of Entity Framework. You must explicitly include the reference to load it into memory. You can to this by using the Include() method as below. I assume that STATUS_DESC is the name of the navigation property. Replace it with the actual one if I'm wrong:
Dim account As STAFF =
(From a In sa.STAFFs Where a.STAFF_NO = staffno Select a) _
.Include("STATUS_DESC") _
.FirstOrDefault
Got around it by adding:
If Not cls.STATUS_DESC Is Nothing Then
end if
to the property call, which seems fairly obvious now I think about it. Is this the most efficient way though, I would have thought that EF would have been able to handle a simple left join.
I'm currently trying to create an Endeca query using the Java API for a URLENEQuery. The current query is:
collection()/record[CONTACT_ID = "xxxxx" and SALES_OFFICE = "yyyy"]
I need it to be:
collection()/record[(CONTACT_ID = "xxxxx" or CONTACT_ID = "zzzzz") and
SALES_OFFICE = "yyyy"]
Currently this is being done with an ERecSearchList with CONTACT_ID and the string I'm trying to match in an ERecSearch object, but I'm having difficulty figuring out how to get the UrlENEQuery to generate the or in the correct fashion as I have above. Does anyone know how I can do this?
One of us is confused on multiple levels:
Let me try to explain why I am confused:
If Contact_ID and Sales_Office are different dimensions, where Contact_ID is a multi-or dimension, then you don't need to use EQL (the xpath like language) to do anything. Just select the appropriate dimension values and your navigation state will reflect the query you are trying to build with XPATH. IE CONTACT_IDs "ORed together" with SALES_OFFICE "ANDed".
If you do have to use EQL, then the only way to modify it (provided that you have to modify it from the returned results) is via string manipulation.
ERecSearchList gives you ability to use "Search Within" functionality which functions completely different from the EQL filtering, though you can achieve similar results by using tricks like searching only specified field (which would be separate from the generic search interface") I am still not sure what's the connection between ERecSearchList and the EQL expression above?
Having expressed my confusion, I think what you need to do is to use String manipulation to dynamically build the EQL expression and add it to the Query.
A code example of what you are doing would be extremely helpful as well.
I have a table articles (:Rails Model but I think the issue is more SQL related) which have a column name permalink. To instance, some of my permalinks :
title-of-article
great-article
great-article-about-obama
obama-stuff-about-him
I want to match a request like great-article-about-obama-random-stuff to great-article-about-obama. Is it possible to do it, avoiding killing performance ?
Thanks to all,
ps : We use Rails 3 and Postgresql (or Sqlite not decided yet for production)
EDIT
We can do something like this, but the main downside is we have to fetched every single permalinks from the table articles :
permalinks = ['title-of-article','great-article','great-article-about-obama','obama-stuff-about-him']
string_to_match = 'great-article-about-obama-random-stuf'
result = permalinks.inject('') do |matched,permalink|
matched = (string_to_match.include? permalink and permalink.size > matched.size) ? permalink : matched
end
result => 'great-article-about-obama'
I'll love to find a way to do it directly in SQL for obvious performance reason.
Unless using a text-search base technology (w/ postgres : http://www.postgresql.org/docs/8.3/static/textsearch-dictionaries.html + http://tenderlovemaking.com/2009/10/17/full-text-search-on-heroku/ or solr, indexTank) you can do it with :
request = "chien-qui-aboie"
article = nil
while !article do
article = Article.where("permalink like ?", request+"%").select(:id).first
request.gsub!(/-[^-]*$/) unless article
end
This will first look for chien-qui-aboie%, then chien-qui%, then chien%.
This will also match "chien_qui_mange" if there is an article "chien_qui_mange" but no one about "chien qui aboie"
That's not optimal because of the number of requests, but that's not that heavy if it's just a look up, and not the normal way of accessing a record.