SOLR - Best approach to import 20 million documents from csv file

Question

My current task on hand is to figure out the best approach to load millions of documents in solr. The data file is an export from DB in csv format.

Currently, I am t

Answer 1

Unless a database is already part of your solution, I wouldn't add additional complexity to your solution. Quoting the SOLR FAQ it's your servlet container that is issuing the session time-out.

As I see it, you have a couple of options (In my order of preference):

Increase container timeout

Increase the container timeout. ("maxIdleTime" parameter, if you're using the embedded Jetty instance).

I'm assuming you only occasionally index such large files? Increasing the time-out temporarily might just be simplest option.

Split the file

Here's the simple unix script that will do the job (Splitting the file in 500,000 line chunks):

split -d -l 500000 data.csv split_files.
for file in `ls split_files.*`
do  
curl 'http://localhost:8983/solr/update/csv?fieldnames=id,name,category&commit=true' -H 'Content-type:text/plain; charset=utf-8' --data-binary @$file
done

Parse the file and load in chunks

The following groovy script uses opencsv and solrj to parse the CSV file and commit changes to Solr every 500,000 lines.

import au.com.bytecode.opencsv.CSVReader

import org.apache.solr.client.solrj.SolrServer
import org.apache.solr.client.solrj.impl.CommonsHttpSolrServer
import org.apache.solr.common.SolrInputDocument

@Grapes([
    @Grab(group='net.sf.opencsv', module='opencsv', version='2.3'),
    @Grab(group='org.apache.solr', module='solr-solrj', version='3.5.0'),
    @Grab(group='ch.qos.logback', module='logback-classic', version='1.0.0'),
])

SolrServer server = new CommonsHttpSolrServer("http://localhost:8983/solr/");

new File("data.csv").withReader { reader ->
    CSVReader csv = new CSVReader(reader)
    String[] result
    Integer count = 1
    Integer chunkSize = 500000

    while (result = csv.readNext()) {
        SolrInputDocument doc = new SolrInputDocument();

        doc.addField("id",         result[0])
        doc.addField("name_s",     result[1])
        doc.addField("category_s", result[2])

        server.add(doc)

        if (count.mod(chunkSize) == 0) {
            server.commit()
        }
        count++
    }
    server.commit()
}