Here is the single line from one of my functions to test if any objects in my array have a given property with a matching value
Return ((From tag In DataCache.Tags Where (tag.FldTag = strtagname) Select tag).Count = 1)
WHERE....
DataCache.Tags is an array of custom objects
strtagname = "brazil"
and brazil is definitely a tag name stored within one of the custom objects in the array.
However the function continually returns false.
Can someone confirm to me that the above should or should not work.
and if it wont work can someone tell me the best way to test if any of the objects in the array contain a property with a specific value.
I suppose in summary I am looking for the equivalent of a SQL EXISTS statement.
Many thanks in hope.
Your code is currently checking whether the count is exactly one.
The equivalent of EXISTS in LINQ is Any. You want something like:
Return DataCache.Tags.Any(Function(tag) tag.FldTag = strtagname)
(Miraculously it looks like that syntax may be about right... it looks like the docs examples...)
Many Thanks for the response.
Your code did not work. Then I realised that I was comparing to an array value so it would be case sensitive.
However glad I asked the question, as I found a better way than mine.
Many thanks again !
Related
I'm having an issue getting a query to work.
I'm essentially trying to write something like the following SQL, with the literal 5 replaced with a variable:
SELECT *
FROM "my_table"
WHERE 5 BETWEEN "my_table"."minimum" AND "my_table"."maximum"
This is what I have at the moment:
MyModel.where(
Arel::Nodes::Between.new(
my_variable, (MyModel.arel_table[:minimum]).and(MyModel.arel_table[:maximum])
)
)
Please ignore the way I am using arel_table, the actual query has multiple joins and is more complex, but this is the most minimum reproducible example I have to demonstrate the problem.
The error, as in the subject of the question is as follows:
undefined method `and' for #<Arel::Attributes::Attribute:0x00007f55e15514f8>
and method is for Arel::Nodes::Node i.e. MyModel.arel_attribute[:name].eq(Arel::Nodes::Quoted.new('engineersmnky')) This is an Arel::Nodes::Equality and you can chain with and.
That being said you can construct an Arel::Nodes::And for yourself via
Arel::Nodes::And.new([left,right])
Then we can pass this to the Between class like so
Arel::Nodes::Between.new(
Arel::Nodes::Quoted.new(my_variable),
Arel::Nodes::And.new([
MyModel.arel_table[:minimum],
MyModel.arel_table[:maximum]])
)
The Arel::Nodes::Quoted (also: Arel::Nodes.build_quoted(arg)) is not needed in your case since your my_variable is an Integer which can be visited and will be treated as an Arel::Nodes::SqlLiteral but I find it best to let arel decide how to handle the quoting in case your my_variable ends up being some other un-visitable Object
There are other ways to create a Between and other ways to create an And depending on what objects you are dealing with.
between is a Arel::Predication and these predications are available to Arel::Nodes::Attribute objects e.g.
MyModel.arel_table[:minimum].between([1,6])
and as mentioned is available to Arel::Nodes::Node and instances of this class provides a convenience method (create_and) for creating an And so we could do the following:
Arel::Nodes::Node.new.create_and([
MyModel.arel_table[:minimum],
MyModel.arel_table[:maximum]])
There are a number of other ways to hack this functionality together by using other Arel classes but this should get you headed in the right direction.
TLDR: I have 2 arrays indices = numpy.arange(9) and another that contains some of the numbers in indices (maybe none at all, maybe it'll contain [2,4,7]). The output I'd like for this example is [0,1,3,5,6,8]. What method can be used to achieve this?
Edit: I found a method which works somewhat: casting both arrays to a set then taking the difference of the two does give the correct result, but as a set, even if I pass this result to a numpy.array(). I'll update this if I find a solution for that.
Edit2: Casting the result of the subtraction to a list, then casting passing that to a numpy.array() resolved my issue.
I guess I posted this question a little prematurely, given that I found the solution for it myself, but maybe this'll be useful to somebody in future!
You can make use of boolean masking:-
indices[~numpy.isin(indices,[2,4,7])]
Explanation:-
we are using numpy.isin() method to find out the values exists or not in incides array and then using ~ so that this gives opposite result and finally we are passing this boolean mask to indices
I want to check if an entity is part of the users input.
Example:
entities['#PRODUKT_INTENT_STOP_LIST']?.contains($variables.tmpEntity)
As you can see by this example, the value of the entity#PRODUKT_INTENT_STOP_LIST
is a variable. I put this at a condition for a node, but this is not working.
If I use a hardcoded string instead of the variable it is working fine.
entities['#PRODUKT_INTENT_STOP_LIST']?.contains('Chart') works fine
but setting $variables.tmpEntity to 'Chart' a and then ask for
entities['#PRODUKT_INTENT_STOP_LIST']?.contains($variables.tmpEntity)
is not working.
Can someone tells me what's wrong here?
Still trying to understand what you are trying to do.But if you want to check whether an entity exist in your input or not you can do it by applying condition on size of that entity.
"context":{
"size":"<?#Entity.size()?>"
}
now if size is equals to 0 then entity does not exist.
I know this is a longer way but it also tells you how many times does that entity exist in your input.
Hi I used the wrong statement.
This statement should work:
entities[PRODUKT_INTENT_STOP_LIST]?.get($variables.countEntity).value==$variables.$variables.tmpEntity
$variables.countEntity : counter to iterate thru entity array #PRODUKT_INTENT_STOP_LIST to check if an entity value is equal $variables.tmpEntity
Regards
I'm new to lucene, day 1 new. So I've read a tutorial on lucene and spent a while trying to work out how to find a non null value in lucene.
So I have a document called Inspect
The document has two fields I'm interested in: Inspect and Direct.
{
"Inspect": "Feather",
"Direct": {}
}
I want to find all documents where Inspect = "Feather" and Direct is not empty.
I am also interested in finding documents where Direct is also empty.
I am doing this in the ravenDB studio, so I am using lucene. I have tried a few things like
Inspect: Feather
And NOT
Direct: [[NULL_VALUE]]
However this doesn't seem to work. Any advice or some direction would be much appreciated.
Cheers
You need to run a query like this:
Inspect: Feather AND NOT Direct.Count: 0
When you are comparing to a null object, it fails, Direct is not null, but with the .Count there you are actually counting the number of properties in the object, which seems to be what you want.
#stacka Hi! I'm also rather new to RavenDB, but I have some ideas that may help you. First of all, use the '-' (minus) character instead of NOT. It's a convention. Second, you may face the problem that query cannot be run against db, when any property is not indexed. So, you should create one including the field you want to query against. Hope, this would help.
I'm new to Lua so please bear with this simple question :)
I'm simply trying to iterate over a table, and modify it's values. however, it seems I can't modify directly the "value" part?
code:
for id,value in pairs(some_table) do
value = value * some_math_here
end
will i actually need to modify some_table[id] instead, or is there a more elegant way?
You will actually need to modify
some_table[id]
instead. value does not actually represent some_table[id]