| = Merging Indexes |
| // Licensed to the Apache Software Foundation (ASF) under one |
| // or more contributor license agreements. See the NOTICE file |
| // distributed with this work for additional information |
| // regarding copyright ownership. The ASF licenses this file |
| // to you under the Apache License, Version 2.0 (the |
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| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
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| |
| If you need to combine indexes from two different projects or from multiple servers previously used in a distributed configuration, you can use either the IndexMergeTool included in `lucene-misc` or the `CoreAdminHandler`. |
| |
| To merge indexes, they must meet these requirements: |
| |
| * The two indexes must be compatible: their schemas should include the same fields and they should analyze fields the same way. |
| * The indexes must not include duplicate data. |
| |
| Optimally, the two indexes should be built using the same schema. |
| |
| == Using IndexMergeTool |
| |
| To merge the indexes, do the following: |
| |
| . Make sure that both indexes you want to merge are closed. |
| . Issue this command: |
| + |
| [source,bash] |
| ---- |
| java -cp $SOLR/server/solr-webapp/webapp/WEB-INF/lib/lucene-core-VERSION.jar:$SOLR/server/solr-webapp/webapp/WEB-INF/lib/lucene-misc-VERSION.jar org/apache/lucene/misc/IndexMergeTool /path/to/newindex /path/to/old/index1 /path/to/old/index2 |
| ---- |
| + |
| This will create a new index at `/path/to/newindex` that contains both index1 and index2. |
| . Copy this new directory to the location of your application's Solr index (move the old one aside first, of course) and start Solr. |
| |
| == Using CoreAdmin |
| |
| The `MERGEINDEXES` command of the <<coreadmin-api.adoc#coreadmin-mergeindexes,CoreAdminHandler>> can be used to merge indexes into a new core – either from one or more arbitrary `indexDir` directories or by merging from one or more existing `srcCore` core names. |
| |
| See the <<coreadmin-api.adoc#coreadmin-mergeindexes,CoreAdminHandler>> section for details. |
