ArangoDB create Vertex REST API without knowing the vertex id's - rest

Is there a way to create with ArangoDB an Edge with REST API without knowing the Vertex ids? With a query to find the vertexs and link them?
Like this with OrientDB: create edge Uses from (select from Module where name = 'm2') to (select from Project where name = 'p1')
I don't want to query via REST the two vertex before, and after create the Edge. I don't want to use Foxx also.
Perhaps with AQL?
Thanks.

Yes, it is doable with a single AQL query:
LET from = (FOR doc IN Module FILTER doc.name == 'm2' RETURN doc._id)
LET to = (FOR doc IN Project FILTER doc.name == 'p1' RETURN doc._id)
INSERT {
_from: from[0],
_to: to[0],
/* insert other edge attributes here as needed */
someOtherAttribute: "someValue"
}
INTO nameOfEdgeCollection

Related

Getting ElasticSearch document fields inside of loaded records in searchkick

Is it possible to get ElasticSearch document fields inside of loaded AR records?
Here is a gist that illustrates what I mean: https://gist.github.com/allomov/39c30905e94c646fb11637b45f43445d
In this case I want to avoid additional computation of total_price after getting response from ES. The solution that I currently see is to include the relationship and run total_price computation for each record, which is not so optimal way to perform this operation, as I see it.
result = Product.search("test", includes: :product_components).response
products_with_total_prices = result.map do |product|
{
product: product
total_price: product.product_components.map(&:price).compact.sum
}
end
Could you please tell if it is possible to mix ES document fields into AR loaded record?
As far as I'm aware it isn't possible to get a response that merges the document fields into the loaded record.
Usually I prefer to completely rely on the data in the indexed document where possible (using load: false as a search option), and only load the AR record(s) as a second step if necessary. For example:
result = Product.search("test", load: false).response
# If you also need AR records, could do something like:
product_ids = result.map(&:id)
products_by_id = {}
Product.where(id: product_ids).find_each do |ar_product|
products_by_id[ar_product.id] = ar_product
end
merged_result = result.map do |es_product|
es_product[:ar_product] = products_by_id[es_product.id]}
end
Additionally, it may be helpful to retrieve the document stored in the ES index for a specific record, which I would normally do by defining the following method in your Product class:
def es_document
return nil unless doc = Product.search_index.retrieve(self).presence
Hashie::Mash.new doc
end
You can use select: true and the with_hit method to get the record and the search document together. For your example:
result = Product.search("test", select: true)
products_with_total_prices =
result.with_hit.map do |product, hit|
{
product: product,
total_price: hit["_source"]["total_price"]
}
end

OrientDB select record count from all graph classes

Any way to get record count for each graph class (V, E and their subclasses)?
I tried to build query in SQL format for current case:
SELECT #class, count(*) FROM V GROUP BY #class
SELECT #class, count(*) FROM E GROUP BY #class
But using count() + GROUP BY is extrimply slow combination.
While console command list classes works fast and return values for count of records in each class (field RECORDS), how to extract this counts via SQL query (or via OrientJS API)?
The main idea is find a way to:
Get list of all classes if database
Get count of records that stored in each class
Technical details
In OrientDB functions you have access to orient variable that have .getDatabase() method. And this method return JAVA ODatabaseDocumentTx class instance. This class provides the method .countClass(className) that returns the number of the records of the class className (method documentation) and it works realy fast.
Solution
Create function in OrientDB Studio with name "getClassCounts", language "javascript", idempotent: true:
var db = orient.getDatabase();
var classesRawInfo = db.getMetadata().getImmutableSchemaSnapshot().getClasses().toArray();
var classesList = {};
var i = classesRawInfo.length;
while(--i) {
var className = classesRawInfo[i].name;
classesList[className] = db.countClass(className);
}
return classesList;
Executing:
via SQL: SELECT getClassCounts()
I think it's not possible, also because it wouldn't so fast as in the console

Tinkerpop Frames #Adjacency to Orientdb LINKLIST

Is there a way to map Tinkerpop Frames's #Adjacency annotated property to Orientdb LINKLIST? Right now I've something like this:
interface Person {
#Adjacency(label = "personCars", direction = Direction.OUT)
Iterable<Car> getCars();
#Adjacency(label = "personCars", direction = Direction.OUT)
void addCar(Car car);
}
I want this to be mapped to LINKLIST in Orientdb database to keep an order of added vertices. But this is by default mapped to LINKBAG type. Is there any clean solution to set Orientdb to map adjacencies to LINKLISTs?
OrientDB, by default, uses a set to handle the edge collection. Sometimes it's better having an ordered list to access the edge by an offset. Example:
person.createEdgeProperty(Direction.OUT, "Photos").setOrdered(true);
Every time you access the edge collection the edges are ordered. Below is an example to print all the photos in an ordered way.
for (Edge e : loadedPerson.getEdges(Direction.OUT, "Photos")) {
System.out.println( "Photo name: " + e.getVertex(Direction.IN).getProperty("name") );
}
To access the underlying edge list you have to use the Document Database API. Here's an example to swap the 10th photo with the last.
// REPLACE EDGE Photos
List<ODocument> photos = loadedPerson.getRecord().field("out_Photos");
photos.add(photos.remove(9));
From the official documentation.

How to insert a vertex with link type property with the orientjs query builder?

I am trying to insert a vertex with orientjs(previously oriento) query builder. My class has a link type property pointing to another class.
I know I can get it to work with a raw query string but I would love to use the query builder.
Here is what I've tried so far :
db.insert()
.into('VertexClassName')
.set({"prop":"value", "linkProperty":"33:1289287"})
db.insert()
.into('VertexClassName')
.set({"prop":"value", "linkProperty":"#33:1289287"})
I get the following error :
Error on saving record in cluster #13
Am I setting properties in the right way ?
Could the error be related to somtehing else ?
I have sucessfully ran an insert query in the cluster #13 with a raw query string in the studio...
According to the official documentation it seems that the problem might be at the end of your statement
db.insert().into('VertexClassName')
.set({"prop":"value", "linkProperty":"33:1289287"}).one()
.then(function (data) {
// callback
});
Check if your code works adding one() to the pipe line
EDITED: I found this method in orientjs.
db.create('VERTEX', 'V')
.set({
key: 'value',
foo: 'bar'
})
.one()
.then(function (vertex) {
console.log('created vertex', vertex);
});
When using Tinkerpop API they recommend using createVertex instead of insert, because createVertex is intended for graphs and insert for Documents... Could you try with the create() method instead?
I am using SQL and it worked.
sql = "INSERT INTO Station set linked = (select from LinkedClass where LinkedProb = 'value'), prop = 'value'"
OrientVertex vertex = new OrientVertex();
vertex = graph.command(new OCommandSQL(sql)).execute();
I don't think that's possible unless you've added a proper field with the right type 'Link' in your schema. (which I rarely do).
Now instead of having the right 'link' type inserted you can do the opposite, store is as a String, and leverage the query functions to use it correctly:
db.insert().into('table').set({prop: '#15:14'}).one();
And it will be converted as String (which is a bit sad) but then you can use that in your queries:
SELECT eval(prop) FROM table;
And it will be 'eval'-ed to a Node RecordID that you can directly use and call functions like expand() on.
For example:
SELECT name FROM (SELECT expand(eval(prop)) FROM table);
Will eval the node stored in the insert(), grab the node, expand it and collect its name property.

Entity Framework, How to include related entities in this example

I have a table AccountSecurity which is a many-to-many table that relates Account entities and Securities. When I write the query below it returns all Securities that satisfy the where clause. However each Security instance in the list no longer has the reference to the AccountSecurity it came from. So when I do list[0].AccountSecurity it is empty. Is there anyway to include that information? I know I can rewrite the query to return AccountSecurities instead and use .Include("Security") on that, but I wonder if it can be done another way.
var list = (from acctSec in base.context.AccountSecurities
where acctSec.AccountId == accountId
select acctSec.Security).ToList();
UPDATE
Of course if I do two queries the graph gets populated properly, there has to be a way to do this in one shot.
var securities = (from acctSec in base.context.AccountSecurities
where acctSec.AccountId == accountId
select acctSec.Security).ToList();
//this query populates the AccountSecurities references within Security instances returned by query above
var xref = (from acctSec in base.context.AccountSecurities
where acctSec.AccountId == accountId
select acctSec).ToList();
var list = (from sec in base.context.Securities
.Include("AccountSecurity")
where sec.AccountSecurities.Any(as => as.AccountId == accountId)
select sec).ToList();
Try this:
var list = (from acctSec in base.context.AccountSecurities.Include("Security")
where acctSec.AccountId == accountId
select acctSec).ToList();
Then simply use the Security property as needed, and since it's read at the same time AccountSecurities is (single SQL with join), it will be very efficient.