Query to support node to node search in neo4jrb - neo4jrb

I have this cypher query of
match p= (START:Task {name: 'Start'})-[*]->(finish:Task {name: 'C'}) return p
and would like to make the related active model query using neo4jrb.

Without more information:
Neo4j::ActiveBase.query("match p= (START:Task {name: 'Start'})-[*]->(finish:Task {name: 'C'}) return p").pluck(:p)
I'm not sure what you mean by "related active model query", but if Task is a ActiveNode model you could also do
Task.query_as(:t).match("p=(t {name: 'Start'})-[*]->(:Task {name: 'C'})").pluck(:p)
But I think the first version is clearer. In both cases you're returning a Neo4j::Core::Path object.

Related

Karate graphql variables inside query

I am trying to insert previously defined variable inside graphql query but I'm not able to find any example on how to do that except creating variables outside of query text and then making request with variables.
There is one problem for me for example in this example
queries: [{type: TERM, match: EQUAL, field: "fieldOne", value: "#(id)"},
{type: TERM, match: EQUAL, field: "fieldTwo", value: null}]
I want to insert value #(id) only for the first object in graphql query. Can anyone please provide some example for me or any suggestions on how to do that?
Alright I was thinking that it will be possible to directly replace text inside query, but I found solution from karate documentation with.
queries: [{type: TERM, match: EQUAL, field: "fieldOne", value: "<id>"},
{type: TERM, match: EQUAL, field: "fieldTwo", value: null}]
enclose id inside query text in angle brackets <> and then replace id inside query with id stored in variable id by calling
* replace query.id = id

Prepend or append to values obtained from Knex js SQL queries

I have a simple people table which has two columns id and name.
I can query all the names along with the id as follows
const persons = await knex('people').select('id','name');
I want to add Dr. in front of all the names.
For example
{id:1, name: 'Tom'}
should return
{id:1, name: 'Dr. Tom'}
How do I do this in knex js ?
I believe you could easily do it in memory using JS map, but apparently you want to do it on db level.
Basically, you need the following query:
select CONCAT('Dr. ', people.name) as 'name', people.id as 'id' from people;
(Tested in w3schools online fiddler)
So, effectively we could try the following (basing on Identifier Syntax from http://knexjs.org/):
knex({ people: 'people' })
.select({
id: 'people.id',
name: 'CONCAT("Dr. ", people.name)'
})
But I'm not sure if knex will substitute it properly.
The problem is, however, that CONCAT is not supported by all SQL dialects, as far as I am concerned.

RedisGraph - Combining multiple directives with MERGE

I am currently running the below query on Neo4J
match (p:Initial{state: 'Initial', name: 'Initial'}), (c:Encounter{code:'abcd', state: 'Encounter', name: 'Encounter1'})
merge (p)-[:raw {person_id:'1234', type:'Encounter', code:'abcd'}]->(c)
However I am unable to do the same query on RedisGraph.
According to what I have found so far, Redis does not seem to support combining MERGEwith other directives
Is there any workaround to this?
Can the query be changed to allow it to execute the same functionality without the match statement?
The only option I see right now is to split this into two queries,
The first one checks to see if p is connected to c:
MATCH (p:Initial{state: 'Initial', name: 'Initial'})-[:raw {person_id:'1234', type:'Encounter', code:'abcd'}]->(c:Encounter{code:'abcd', state: 'Encounter', name: 'Encounter1'}) RETURN p,c
If the above query returns empty issue a second query to form the relation:
MATCH (p:Initial{state: 'Initial', name: 'Initial'})(c:Encounter{code:'abcd', state: 'Encounter', name: 'Encounter1'}) CREATE (p)-[:raw {person_id:'1234', type:'Encounter', code:'abcd'}]->(c)

Neo4j.rb How to use it with Rails

I am using neo4j version 3.X, I am using searchkick
currently using
User.search(params[:term], operator: 'or',
fields: [:first_name, :last_name],
misspellings: { below: 5 },
match: :word_start,
page: params[:page], per_page: params[:rpp], padding: params[:offset])
instead of
User.where('(sp.first_name + sp.last_name) =~ ?', /.*#{params[:term].sub(/\s/, '')}.*/i)
But I have problem where I have to make more cypher queries at the same time with searching How to do that?
For exmaple
Neo4j::ActiveBase.new_query.match(n: {User: { uuid: current_user.uuid }}).break
.match('(n)-[:connected_to {status: 2}]-(sp:User)')
.return('DISTINCT sp')
I want to seach in this query with elasctic search with first name & last name
In my model I have defined searchkick word_start: [:first_name, :last_name]
It's been a while since I've used searchkick, but I would suggest trying to use the ActiveNode syntax instead of the neo4j-core Query syntax so that you can append .search on the end:
current_user.connected_users.rel_where(status: 2).distinct.search(...)
This is assuming that there is a connected_users association which uses the connected_to relationship type. You may have another, similar, association in your User model but I didn't know what it was.
I'm not 100% sure if the distinct will work with the search or not, but you could perhaps drop the .distinct part and searchkick might return you a distinct set anyway.

BigQuery UDF Internal Error

We had a simple UDF in BigQuery that somehow throws an error that keeps returning
Query Failed
Error: An internal error occurred and the request could not be completed.
The query was simply trying to use UDF to perform a SHA256.
SELECT
input AS title,
input_sha256 AS title_sha256
FROM
SHA256(
SELECT
title AS input
FROM
[bigquery-public-data:hacker_news.stories]
GROUP BY
input
)
LIMIT
1000
The in-line UDF is pasted below. However I can not post the full UDF as StackOverflow complaints too much code in the post. The full UDF can be seen this gist.
function sha256(row, emit) {
emit(
{
input: row.input,
input_sha256: CryptoJS.SHA256(row.input).toString(CryptoJS.enc.Hex)
}
);
}
bigquery.defineFunction(
'SHA256', // Name of the function exported to SQL
['input'], // Names of input columns
[
{'name': 'input', 'type': 'string'},
{'name': 'input_sha256', 'type': 'string'}
],
sha256 // Reference to JavaScript UDF
);
Not sure if it helps, but the Job-ID is
bigquery:bquijob_7fd3b51c_153c058dc7c
Looks like there is a similar issue at:
https://code.google.com/p/google-bigquery/issues/detail?id=478
Short answer - this is an issue related to memory allocation that I uncovered via my own testing and fixed today, but it will take a little while to flow out to production.
Slightly longer answer - we just rolled out a fix today for an issue where users who were having "out of memory" issues when scaling up their UDFs over larger number of rows, even though the UDF would succeed on smaller numbers of rows. The queries that were hitting that condition are now running fine on our internal / test trees. However, since public BigQuery hosts have much higher traffic loads, the JavaScript engine that executes the UDFs (V8) behaves somewhat differently in production than it does in internal trees. Specifically, there's a new memory allocation error that some of the previously OOMing jobs are now hitting that we couldn't observe until the queries ran on a fully-loaded tree.
It's a minor error with a quick fix, but we'd ideally let it flow through our regular testing and QA cycle. This should put the fix in production in about a week, assuming nothing else goes wrong with the candidate. Would that be acceptable for you?
i am re-using answer box to provide full query text. it works if uncomment LIMIT 40
SELECT input, input_sha256 FROM JS(
(
SELECT title AS input
FROM [bigquery-public-data:hacker_news.stories]
GROUP BY input
//LIMIT 40
),
input,
"[ {'name': 'input', 'type': 'string'}, {'name': 'input_sha256', 'type': 'string'} ] ",
"function(row, emit) {
var CryptoJS=CryptoJS||function(h,s){var f={},g=f.lib={},q=function(){},m=g.Base={extend:function(a){q.prototype=this;var c=new q;a&&c.mixIn(a);c.hasOwnProperty('init')||(c.init=function(){c.$super.init.apply(this,arguments)});c.init.prototype=c;c.$super=this;return c},create:function(){var a=this.extend();a.init.apply(a,arguments);return a},init:function(){},mixIn:function(a){for(var c in a)a.hasOwnProperty(c)&&(this[c]=a[c]);a.hasOwnProperty('toString')&&(this.toString=a.toString)},clone:function(){return this.init.prototype.extend(this)}}, r=g.WordArray=m.extend({init:function(a,c){a=this.words=a||[];this.sigBytes=c!=s?c:4*a.length},toString:function(a){return(a||k).stringify(this)},concat:function(a){var c=this.words,d=a.words,b=this.sigBytes;a=a.sigBytes;this.clamp();if(b%4)for(var e=0;e<a;e++)c[b+e>>>2]|=(d[e>>>2]>>>24-8*(e%4)&255)<<24-8*((b+e)%4);else if(65535<d.length)for(e=0;e<a;e+=4)c[b+e>>>2]=d[e>>>2];else c.push.apply(c,d);this.sigBytes+=a;return this},clamp:function(){var a=this.words,c=this.sigBytes;a[c>>>2]&=4294967295<< 32-8*(c%4);a.length=h.ceil(c/4)},clone:function(){var a=m.clone.call(this);a.words=this.words.slice(0);return a},random:function(a){for(var c=[],d=0;d<a;d+=4)c.push(4294967296*h.random()|0);return new r.init(c,a)}}),l=f.enc={},k=l.Hex={stringify:function(a){var c=a.words;a=a.sigBytes;for(var d=[],b=0;b<a;b++){var e=c[b>>>2]>>>24-8*(b%4)&255;d.push((e>>>4).toString(16));d.push((e&15).toString(16))}return d.join('')},parse:function(a){for(var c=a.length,d=[],b=0;b<c;b+=2)d[b>>>3]|=parseInt(a.substr(b, 2),16)<<24-4*(b%8);return new r.init(d,c/2)}},n=l.Latin1={stringify:function(a){var c=a.words;a=a.sigBytes;for(var d=[],b=0;b<a;b++)d.push(String.fromCharCode(c[b>>>2]>>>24-8*(b%4)&255));return d.join('')},parse:function(a){for(var c=a.length,d=[],b=0;b<c;b++)d[b>>>2]|=(a.charCodeAt(b)&255)<<24-8*(b%4);return new r.init(d,c)}},j=l.Utf8={stringify:function(a){try{return decodeURIComponent(escape(n.stringify(a)))}catch(c){throw Error('Malformed UTF-8 data');}},parse:function(a){return n.parse(unescape(encodeURIComponent(a)))}}, u=g.BufferedBlockAlgorithm=m.extend({reset:function(){this._data=new r.init;this._nDataBytes=0},_append:function(a){'string'==typeof a&&(a=j.parse(a));this._data.concat(a);this._nDataBytes+=a.sigBytes},_process:function(a){var c=this._data,d=c.words,b=c.sigBytes,e=this.blockSize,f=b/(4*e),f=a?h.ceil(f):h.max((f|0)-this._minBufferSize,0);a=f*e;b=h.min(4*a,b);if(a){for(var g=0;g<a;g+=e)this._doProcessBlock(d,g);g=d.splice(0,a);c.sigBytes-=b}return new r.init(g,b)},clone:function(){var a=m.clone.call(this); a._data=this._data.clone();return a},_minBufferSize:0});g.Hasher=u.extend({cfg:m.extend(),init:function(a){this.cfg=this.cfg.extend(a);this.reset()},reset:function(){u.reset.call(this);this._doReset()},update:function(a){this._append(a);this._process();return this},finalize:function(a){a&&this._append(a);return this._doFinalize()},blockSize:16,_createHelper:function(a){return function(c,d){return(new a.init(d)).finalize(c)}},_createHmacHelper:function(a){return function(c,d){return(new t.HMAC.init(a, d)).finalize(c)}}});var t=f.algo={};return f}(Math);
(function(h){for(var s=CryptoJS,f=s.lib,g=f.WordArray,q=f.Hasher,f=s.algo,m=[],r=[],l=function(a){return 4294967296*(a-(a|0))|0},k=2,n=0;64>n;){var j;a:{j=k;for(var u=h.sqrt(j),t=2;t<=u;t++)if(!(j%t)){j=!1;break a}j=!0}j&&(8>n&&(m[n]=l(h.pow(k,0.5))),r[n]=l(h.pow(k,1/3)),n++);k++}var a=[],f=f.SHA256=q.extend({_doReset:function(){this._hash=new g.init(m.slice(0))},_doProcessBlock:function(c,d){for(var b=this._hash.words,e=b[0],f=b[1],g=b[2],j=b[3],h=b[4],m=b[5],n=b[6],q=b[7],p=0;64>p;p++){if(16>p)a[p]= c[d+p]|0;else{var k=a[p-15],l=a[p-2];a[p]=((k<<25|k>>>7)^(k<<14|k>>>18)^k>>>3)+a[p-7]+((l<<15|l>>>17)^(l<<13|l>>>19)^l>>>10)+a[p-16]}k=q+((h<<26|h>>>6)^(h<<21|h>>>11)^(h<<7|h>>>25))+(h&m^~h&n)+r[p]+a[p];l=((e<<30|e>>>2)^(e<<19|e>>>13)^(e<<10|e>>>22))+(e&f^e&g^f&g);q=n;n=m;m=h;h=j+k|0;j=g;g=f;f=e;e=k+l|0}b[0]=b[0]+e|0;b[1]=b[1]+f|0;b[2]=b[2]+g|0;b[3]=b[3]+j|0;b[4]=b[4]+h|0;b[5]=b[5]+m|0;b[6]=b[6]+n|0;b[7]=b[7]+q|0},_doFinalize:function(){var a=this._data,d=a.words,b=8*this._nDataBytes,e=8*a.sigBytes; d[e>>>5]|=128<<24-e%32;d[(e+64>>>9<<4)+14]=h.floor(b/4294967296);d[(e+64>>>9<<4)+15]=b;a.sigBytes=4*d.length;this._process();return this._hash},clone:function(){var a=q.clone.call(this);a._hash=this._hash.clone();return a}});s.SHA256=q._createHelper(f);s.HmacSHA256=q._createHmacHelper(f)})(Math);
(function(){var h=CryptoJS,j=h.lib.WordArray;h.enc.Base64={stringify:function(b){var e=b.words,f=b.sigBytes,c=this._map;b.clamp();b=[];for(var a=0;a<f;a+=3)for(var d=(e[a>>>2]>>>24-8*(a%4)&255)<<16|(e[a+1>>>2]>>>24-8*((a+1)%4)&255)<<8|e[a+2>>>2]>>>24-8*((a+2)%4)&255,g=0;4>g&&a+0.75*g<f;g++)b.push(c.charAt(d>>>6*(3-g)&63));if(e=c.charAt(64))for(;b.length%4;)b.push(e);return b.join('')},parse:function(b){var e=b.length,f=this._map,c=f.charAt(64);c&&(c=b.indexOf(c),-1!=c&&(e=c));for(var c=[],a=0,d=0;d< e;d++)if(d%4){var g=f.indexOf(b.charAt(d-1))<<2*(d%4),h=f.indexOf(b.charAt(d))>>>6-2*(d%4);c[a>>>2]|=(g|h)<<24-8*(a%4);a++}return j.create(c,a)},_map:'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/='}})();
emit( { input: row.input, input_sha256: CryptoJS.SHA256(row.input).toString(CryptoJS.enc.Hex) } );
}"
)