I am using node-red to communicate with cloudant and for each time my flow runs I might have different amount of id:s coming in msg.payload. Later I want to use these id:s to display all the relevant objects. Is it possible to search for multiple id:s in some way? Or do you have any other solution? Can't find anything about this online atm
It looks like Node-RED supports querying by _id, a search index, or all documents. When you use _id there does not seem to be a way to specify more than one ID. You can use a search index, however, to query for multiple IDs.
Create a search index in Cloudant similar to the following:
{
"_id": "_design/allDocSearch",
"views": {},
"language": "javascript",
"indexes": {
"byId": {
"analyzer": "standard",
"index": "function (doc) {\n index(\"id\", doc._id);\n}"
}
}
}
This corresponds to the following when using the Cloudant dashboard:
design doc = allDocSearch
index name = byId
index function =
function (doc) {
index("name", doc.name);
}
To search for multiple IDs your query would look something like this:
id:"1" OR id:"2"
In Node-Red set up your Cloudant node to point to the appropriate database, specify a "Search by" of search index, and configure your design document and index name (in this case it would be allDocSearch/byId).
You can test with a simple inject node with a payload similar to the search query above: id:"1" OR id:"2"
Related
I have Alfresco 7.0 community edition, with search services version 2.0.2.
My need is to search for all documents having some metadata values, both in the version store and the content store.
I've tryied to search against the versionStore from public api with the following body
{
"query": {
"language": "afts",
"query": "TYPE:\"myc:projects\" AND myc:prop:\"pippo\""
},
"paging": {
"maxItems": 100,
"skipCount": 0
},
"include": [
"allowableOperations",
"properties"
],
"scope": {
"locations": "versions"
}
}
but I get http status 500.
If I try to search from Node Browser I receive this error message No solr query support for store workspace://version2Store.
I also tried the ligthweigth store (which is the difference?)
Is it possible to search with lucene, AFTS against the versions? Do I need to enable some property in alfresco-global.properties?
I've also seen this question and it's seems to me they can do searches.
Thanks a lot.
I've been able to handle both types of searches doing a CMIS query, but I had to write a module that handle that type of reseach (the form, results to be joined and displayed...).
Versioned nodes have a property which point to the noreRef of the current node.
Follwing statement find all profiles that has Facebook or twitter and this works:
$filter=SocialAccounts/any(x: search.in(x, 'Facebook,Twitter'))
But I cant find any samples for finding all that has both Facebook and twitter. I tried:
$filter=SocialAccounts/all(x: search.in(x, 'Facebook,Twitter'))
But this is not valid query.
Azure Search does not support the type of ‘all’ filter that you’re looking for. Using search.in with ‘all’ would be equivalent to using OR, but Azure Search can only handle AND in the body of an ‘all’ lambda (which is equivalent to OR in the body of an ‘any’ lambda).
You might try a workaround like this:
$filter=tags/any(t: t eq 'Facebook') and tags/any(t: t eq 'Twitter')
However, this isn't actually equivalent to using all with search.in. The query as expressed using all is matching documents where every social account is strictly either Facebook or Twitter. If any other social account is present, the document won’t match. The workaround doesn’t have this property. A document must have at least Facebook and Twitter in order to match, but not exclusively those. This is certainly a valid scenario; it just isn't the same as using all with search.in, which was the original question.
No matter how you try to rewrite the query, you won’t be able to express an equivalent to the all query. This is a limitation due to the way Azure Search stores collections of strings and other primitive types in the inverted index.
Please vote on user voice to help prioritize:
https://feedback.azure.com/forums/263029-azure-search/suggestions/37166749-efficient-way-to-express-a-true-all
A possible workaround is to use the new Complex Types feature, which does allow more expressive filters inside lambda expressions. For example, if you model tags as objects with a single value property instead of as a collection of strings, you should be able to execute a filter like this:
$filter=tags/all(t: search.in(t/value, 'Facebook,Twitter'))
In the REST API, you'd define tags like this:
{
"name": "myindex",
"fields": [
...
{
"name": "tags",
"type": "Collection(Edm.ComplexType)",
"fields": [
{ "name": "value", "type": "Edm.String", "filterable": true }
]
}
]
}
Note that this feature is in preview at the time of this writing, but will be generally available (and publicly documented) soon.
I'm using couchdb to store large documents, which is causing some trouble when fetching them to memory. I do realize the database is not meant to be used this way. As a fallback solution, is it possible to fetch partial documents from the database, without creating a view?
In example, if a document has the fields id, content and extra_content, I would like to retrieve only the first two.
Thank you in advance.
If you are using CouchDB 2.x, you can use /db/_find endpoint as a mechanism to retrieve part of the doc.
POST /db/_find
{
"selector": {
"_id": "a-doc-id"
},
"fields": [
"_id",
"content"
]
}
You'll get only the set of fields you have specified in the query
This is not possible prior to CouchDB 2.x. For CouchDB 2.x or greater, see JuanjoRodriguez's answer.
But one possible work around for any version of CouchDB would be to take advantage of file attachments, which by default are excluded from a fetch. If some of your data isn't always needed, and doesn't need to be included in indexes, you could potentially store it as (JSON) attachments, rather than as part of the document directly:
{
"id": "foo",
"content": "stuff",
"extra_content": "other stuff"
}
becomes:
{
"id": "foo",
"content": "stuff",
"_attachments": {
"extra_content": {
"content_type": "application/json",
"data": "ZXh0cmEgc3R1ZmYK"
}
}
}
I am using Cloudant database and I would like to retrieve all the documents within the db that match specific fields.
I mean - I'd want to get only those documents which have some fields with specific values that I put.
Could you please help me with an example of code I can test?
Thanks in advance
A good, but quite general question.
You can achieve this in several ways. The most canonical CouchDB way would be to create a map-reduce view (secondary index) keyed on the field you wish to be able to query on, for example:
function (doc) {
if (doc && doc.surname) {
emit(doc.surname, 1);
}
}
You can create such views using the Cloudant dashboard:
You can now query this for all documents with a particular surname:
curl 'https://ACCOUNT.cloudant.com/examples/_design/example/_view/by_surname?limit=100&reduce=false&include_docs=true&startkey="kruger"&endkey="kruger0"'
If you want to be able to query on a combination of fields, you can create a vector-valued key:
function (doc) {
if (doc && doc.surname && doc.firstname) {
emit([doc.surname, doc.firstname], 1);
}
}
which is queried as this:
curl 'https://ACCOUNT.cloudant.com/examples/_design/example/_view/by_name?limit=100&reduce=false&include_docs=true&startkey=\["kruger", "stefan"\]&endkey=\["kruger","stefan0"\]'
If you're new to Cloudant, another way to query is by using the aptly named Cloudant Query (a.k.a. Mango), which is a json-based declarative query language.
It is well documented (https://console.bluemix.net/docs/services/Cloudant/api/cloudant_query.html), but the gist of it is queries of the type:
{
"selector": {
"year": {
"$gt": 2010
}
},
"fields": ["_id", "_rev", "year", "title"],
"sort": [{"year": "asc"}],
"limit": 10,
"skip": 0
}
what seemed a simple task, came to be a challenge for me.
I have the following mongodb structure:
{
(...)
"services": {
"TCP80": {
"data": [{
"status": 1,
"delay": 3.87,
"ts": 1308056460
},{
"status": 1,
"delay": 2.83,
"ts": 1308058080
},{
"status": 1,
"delay": 5.77,
"ts": 1308060720
}]
}
}}
Now, the following query returns whole document:
{ 'services.TCP80.data.ts':{$gt:1308067020} }
I wonder - is it possible for me to receive only those "data" array entries matching $gt criteria (kind of shrinked doc)?
I was considering MapReduce, but could not locate even a single example on how to pass external arguments (timestamp) to Map() function. (This feature was added in 1.1.4 https://jira.mongodb.org/browse/SERVER-401)
Also, there's always an alternative to write storedJs function, but since we speak of large quantities of data, db-locks can't be tolerated here.
Most likely I'll have to redesign the structure to something 1-level deep, like:
{
status:1,delay:3.87,ts:138056460,service:TCP80
},{
status:1,delay:2.83,ts:1308058080,service:TCP80
},{
status:1,delay:5.77,ts:1308060720,service:TCP80
}
but DB will grow dramatically, since "service" is only one of many options which will append each document.
please advice!
thanks in advance
In version 2.1 with the aggregation framework you are now able to do this:
1: db.test.aggregate(
2: {$match : {}},
3: {$unwind: "$services.TCP80.data"},
4: {$match: {"services.TCP80.data.ts": {$gte: 1308060720}}}
5: );
You can use a custom criteria in line 2 to filter the parent documents. If you don't want to filter them, just leave line 2 out.
This is not currently supported. By default you will always receive the whole document/array unless you use field restrictions or the $slice operator. Currently these tools do not allow filtering the array elements based on the search criteria.
You should watch this request for a way to do this: https://jira.mongodb.org/browse/SERVER-828
I'm attempting to do something similar. I tried your suggestion of using the GROUP function, but I couldn't keep the embedded documents separate or was doing something incorrectly.
I needed to pull/get a subset of embedded documents by ID. Here's how I did it using Map/Reduce:
db.parent.mapReduce(
function(parent_id, child_ids){
if(this._id == parent_id)
emit(this._id, {children: this.children, ids: child_ids})
},
function(key, values){
var toReturn = [];
values[0].children.forEach(function(child){
if(values[0].ids.indexOf(product._id.toString()) != -1)
toReturn.push(child);
});
return {children: toReturn};
},
{
mapparams: [
"4d93b112c68c993eae000001", //example parent id
["4d97963ec68c99528d000007", "4debbfd5c68c991bba000014"] //example embedded children ids
]
}
).find()
I've abstracted my collection name to 'parent' and it's embedded documents to 'children'. I pass in two parameters: The parent document ID and an array of the embedded document IDs that I want to retrieve from the parent. Those parameters are passed in as the third parameter to the mapReduce function.
In the map function I find the parent document in the collection (which I'm pretty sure uses the _id index) and emit its id and children to the reduce function.
In the reduce function, I take the passed in document and loop through each of the children, collecting the ones with the desired ID. Looping through all the children is not ideal, but I don't know of another way to find by ID on an embedded document.
I also assume in the reduce function that there is only one document emitted since I'm searching by ID. If you expect more than one parent_id to match, than you will have to loop through the values array in the reduce function.
I hope this helps someone out there, as I googled everywhere with no results. Hopefully we'll see a built in feature soon from MongoDB, but until then I have to use this.
Fadi, as for "keeping embedded documents separate" - group should handle this with no issues
function getServiceData(collection, criteria) {
var res=db[collection].group({
cond: criteria,
initial: {vals:[],globalVar:0},
reduce: function(doc, out) {
if (out.globalVar%2==0)
out.vals.push({doc.whatever.kind.and.depth);
out.globalVar++;
},
finalize: function(out) {
if (vals.length==0)
out.vals='sorry, no data';
return out.vals;
}
});
return res[0];
};