Multiple commits to neo4j from R - r

Question

I have collected some tweets using the twitteR package and thereafter exported them to a neo4j database using Nicole White's various tutorials. I extract the tweets to a dataframe called kdf and thereafter use functions from stringr for basic cleaning up as demonstrated by Nicole. I am then sending this to neo4j from R. The essential part of my code is:
library(RNeo4j)
graph = startGraph("http://localhost:7474/db/data/", username="xxxx", password="xxxx")
clear(graph)
addConstraint(graph, "Tweet", "id")
addConstraint(graph, "User", "username")
addConstraint(graph, "Hashtag", "hashtag")
addConstraint(graph, "Tags", "ent_tag")
query = "
CREATE (tweet:Tweet {id: {tweetID}})
SET tweet.text = {text}
CREATE (user:User {name: {Username}})
CREATE (user)-[:TWEETED]->(tweet)
FOREACH(reply_to_sn IN CASE {reply_to_sn} WHEN NULL then [] else [{reply_to_sn}] END |
MERGE (replytouser:User {username:{reply_to_sn}})
CREATE (tweet)-[:IN_REPLY_TO]->(replytouser)
)
FOREACH(retweet_sn IN CASE {retweet_sn} WHEN NULL THEN [] ELSE [{retweet_sn}] END |
MERGE(retweet_user:User {username: {retweet_sn}})
CREATE (tweet)-[:RETWEET_OF]->(retweet_user)
)
FOREACH(hastag_nodes IN CASE {hashtag_nodes} WHEN NULL then [] else [{hashtag_nodes}] END |
MERGE (h:Hashtag {hashtag :{hashtag_nodes}})
CREATE (tweet)-[:HASHTAG]->(h)
)
FOREACH(mentioned_users IN CASE {mentioned_users} WHEN NULL then [] else [{mentioned_users}] END |
MERGE (m:User {username :{mentioned_users}})
CREATE (tweet)-[:MENTIONED]->(m)
)
"
tx = newTransaction(graph)
for(i in 1:nrow(kdf)){
row = kdf[i, ]
appendCypher(tx, query,
tweetID=row$id,
text=row$text,
Username=row$screenName,
reply_to_sn=row$replyToSN,
retweet_sn=getRetweetSN(row$text),
hashtag_nodes=getHashtags(row$text),
mentioned_users=getMentions(row$text))
}
commit(tx)
What I have done thereafter is extracted named entities for all the text using Watson's Alchemy API. This is stored in a dataframe called ent_tbl. This contains three variables, tweetid, etext and etype. Now I am trying to export this data too to the same neo4j databse and join on the id of the tweets. This is the other part of the code:
query="
MATCH(t:ent_tag {id : $twid, type :$etype, text :$etext})
MATCH(tw:tweet {tweetID : $twid })
CREATE (tw)-[:HAS_ENT]->(t)
"
tx=newTransaction(graph)
for (i in 1:nrow(ent_tbl)){
row = ent_tbl[i,]
appendCypher(tx, query,
twid=row2$tweetid,
etype=row2$etype,
etext=row2$etext)
}
commit(tx)
While I do not get any errors on committing this, summary(graph) does not show me the relationship between the tags (t) and the tweets (tw) that I expected to see.
> summary(graph)
This To That
1 User TWEETED Tweet
2 Tweet RETWEET_OF User
3 Tweet HASHTAG Hashtag
4 Tweet MENTIONED User
5 Tweet IN_REPLY_TO User
Why would this happen?
This is my db.schema in neo4j:

Answer 1

That is because the MATCH does not find any tag or tweet so it breaks. If you want to add data to existing nodes, you should match them by ID and then set their properties. And you got to be consistent with labels and upper/lower cases. I think this is what you are looking for.
query="
MATCH(t:Tags {ent_tag : $twid})
MATCH(tw:Tweet {tweetID : $twid })
SET t.type=$etype, t.text=$etext
CREATE (tw)-[:HAS_ENT]->(t)
"
tx=newTransaction(graph)
for (i in 1:nrow(ent_tbl)){
row = ent_tbl[i,]
appendCypher(tx, query,
twid=row2$tweetid,
etype=row2$etype,
etext=row2$etext)
}
commit(tx)