Solr 4.2 - what is _version_field?
Solution 1
The _version_
field is an internal field that is used by the partial update procedure, the update log process, and by SolrCloud. It is only used internally for those processes, and simply providing the _version_
field in your schema.xml should be sufficient.
If you'd like information as to exactly what is going on with _version_
, you can visit this website to learn about the "optimistic concurrency" update process, which uses _version_
.
Solution 2
add the below field definition inside "field" tag in schema.xml
<field name="_version_" type="long" indexed="true" stored="true" multiValued="false"/>
Solution 3
If you remove it, you must also remove the transaction logging from solrconfig.xml. See the link.
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meghana
Updated on October 30, 2022Comments
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meghana over 1 year
I am getting below error in my solr configuration.
Caused by: org.apache.solr.common.SolrException: Unable to use updateLog: _version_field must exist in schema, using indexed="true" stored="true" and multiValued="false" (_version_ does not exist) at org.apache.solr.core.SolrCore.<init>(SolrCore.java:806) at org.apache.solr.core.SolrCore.<init>(SolrCore.java:619) at org.apache.solr.core.CoreContainer.createFromLocal(CoreContainer.java:1021) at org.apache.solr.core.CoreContainer.create(CoreContainer.java:1051) ... 10 more Caused by: org.apache.solr.common.SolrException: Unable to use updateLog: _version_field must exist in schema, using indexed="true" stored="true" and multiValued="false" (_version_ does not exist) at org.apache.solr.update.UpdateLog.init(UpdateLog.java:245) at org.apache.solr.update.UpdateHandler.initLog(UpdateHandler.java:84) at org.apache.solr.update.UpdateHandler.<init>(UpdateHandler.java:134) at org.apache.solr.update.DirectUpdateHandler2.<init>(DirectUpdateHandler2.java:95) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:532) at org.apache.solr.core.SolrCore.createInstance(SolrCore.java:526) at org.apache.solr.core.SolrCore.createUpdateHandler(SolrCore.java:597) at org.apache.solr.core.SolrCore.<init>(SolrCore.java:790) ... 13 more Caused by: org.apache.solr.common.SolrException: _version_field must exist in schema, using indexed="true" stored="true" and multiValued="false" (_version_ does not exist) at org.apache.solr.update.VersionInfo.getAndCheckVersionField(VersionInfo.java:57) at org.apache.solr.update.VersionInfo.<init>(VersionInfo.java:83) at org.apache.solr.update.UpdateLog.init(UpdateLog.java:242) ... 23 more
I wanted to know that what is
_version_field
, and why its must required ?Can anybody suggest me on this??
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Krunal almost 11 yearsDoes adding this field into the Schema has any impact on the index size?
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Salvatore Iovene over 10 yearsI think you mean
typr="slong"
.long
oesn't appear to work on Solr 4.4. -
ashish about 10 yearsactually there was no need to define version field earlier, it is mandatory when solr added feature to update document partially
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ashish about 10 years@Krunal: what do you think will happen on adding an extra attribute to each document?
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Krunal about 10 years@ashish, we tested this to understand the impact on index size and performance. We found no significant change in index size nor performance. So we decided to left the field into our schema for making it support partial update in future.
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mrmuggles over 8 years@SalvatoreIovene with 4.10, 'slong' didn't work, but 'long' did.
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akaariai about 8 yearsIf you need to use slong or long depends on type definitions inside the <types> element.