# Need to reindex everytime synonym change?
**URL:** https://discuss.elastic.co/t/need-to-reindex-everytime-synonym-change/104482
**Category:** Elasticsearch
**Created:** [October 19, 2017, 3:24am UTC](https://discuss.elastic.co/t/need-to-reindex-everytime-synonym-change/104482 "2017-10-19T03:24:51Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@zidane28](https://discuss.elastic.co/u/zidane28)
#### Post date: [October 19, 2017, 3:24am UTC](https://discuss.elastic.co/t/need-to-reindex-everytime-synonym-change/104482/1 "2017-10-19T03:24:51Z")
All this while my knowledge on synonym is, whenever there is a change in synonym file, I will need to reindex for the changes to kicks in...
But is that still true? Is that possible to not need to reindex whenever there is a change in synonym file but still the changes can be detected in my index?
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### Author:  [@Igor\_Motov](https://discuss.elastic.co/u/Igor_Motov)
#### Post date: [October 22, 2017, 12:21pm UTC](https://discuss.elastic.co/t/need-to-reindex-everytime-synonym-change/104482/2 "2017-10-22T12:21:20Z")
There is no automatic mechanism that would tell you if reindexing is required or not. In general if you are changing index-time synonyms for a word that already was indexed, you need to reindex, but you will need to make this determination yourself. So, to be on the safe side, you need to reindex every time you touch index-time synonyms. You can also switch to search-time only synonyms, then all you will have to do is close and open index.
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### Author:  [@zidane28](https://discuss.elastic.co/u/zidane28)
#### Post date: [October 24, 2017, 8:21am UTC](https://discuss.elastic.co/t/need-to-reindex-everytime-synonym-change/104482/3 "2017-10-24T08:21:03Z")
Thanks for the reply! The only concern if I change to query time synonym would be the search performance...
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### Author:  [@Igor\_Motov](https://discuss.elastic.co/u/Igor_Motov)
#### Post date: [October 24, 2017, 11:51am UTC](https://discuss.elastic.co/t/need-to-reindex-everytime-synonym-change/104482/4 "2017-10-24T11:51:00Z")
It depends on the data and how many synonyms your terms are typically getting resolved into, etc. You can test it to see if slow down is noticeable. On the other side, your index size will be smaller, so more terms will be able to fit into file system cache, so it's not all bad 🙂
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### Author:  [@system](https://discuss.elastic.co/u/system)
#### Post date: [November 21, 2017, 11:51am UTC](https://discuss.elastic.co/t/need-to-reindex-everytime-synonym-change/104482/5 "2017-11-21T11:51:58Z")
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