# How does sql\_last\_value parameter work in jdbc input plugin?
**URL:** https://discuss.elastic.co/t/how-does-sql-last-value-parameter-work-in-jdbc-input-plugin/101624
**Category:** Logstash
**Created:** [September 25, 2017, 3:43am UTC](https://discuss.elastic.co/t/how-does-sql-last-value-parameter-work-in-jdbc-input-plugin/101624 "2017-09-25T03:43:13Z")
**Posts on this page:** 10
**Page:** 1
### Author:  [@amruth](https://discuss.elastic.co/u/amruth)
#### Post date: [September 25, 2017, 3:43am UTC](https://discuss.elastic.co/t/how-does-sql-last-value-parameter-work-in-jdbc-input-plugin/101624/1 "2017-09-25T03:43:13Z")
Hi,
I am using JDBC input plugin with
use\_column\_value =\> true
tracking\_column =\> "id".
But the problem is that my id column is not an incremental all the time. For example it may be as 1,2,3,5,6,7,10,9,8. So what does the file for last\_run\_metadata\_path contain? 8 or 10?
Can someone please help me understand this?
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### Author:  [@magnusbaeck](https://discuss.elastic.co/u/magnusbaeck)
#### Post date: [September 25, 2017, 5:45am UTC](https://discuss.elastic.co/t/how-does-sql-last-value-parameter-work-in-jdbc-input-plugin/101624/2 "2017-09-25T05:45:58Z")
It'll contain 8 since it's the last value seens that's recorded. Can't you just sort on the id column to make sure the values are delivered in order?
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### Author:  [@amruth](https://discuss.elastic.co/u/amruth)
#### Post date: [September 25, 2017, 2:55pm UTC](https://discuss.elastic.co/t/how-does-sql-last-value-parameter-work-in-jdbc-input-plugin/101624/3 "2017-09-25T14:55:01Z")
Hi Magnus,
Coming to the real scenario,
Total number of rows = 3294
Last value I see in the row = 3178
Value in last\_run\_metadat\_path file = --- 3294
Count I see in Elasticsearch(from Kibana) = 3541
I don't quite understand the logic here. Can you please explain?
Thanks
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### Author:  [@magnusbaeck](https://discuss.elastic.co/u/magnusbaeck)
#### Post date: [September 25, 2017, 7:32pm UTC](https://discuss.elastic.co/t/how-does-sql-last-value-parameter-work-in-jdbc-input-plugin/101624/4 "2017-09-25T19:32:20Z")
> Total number of rows = 3294
> Last value I see in the row = 3178
> Value in last\_run\_metadat\_path file = --- 3294
And what query did you end up using?
> Count I see in Elasticsearch(from Kibana) = 3541
Well, I can't tell you what those extra 250 documents come from. Are you sure you started with an empty index? What does your elasticsearch output configuration look like?
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### Author:  [@amruth](https://discuss.elastic.co/u/amruth)
#### Post date: [September 26, 2017, 1:53am UTC](https://discuss.elastic.co/t/how-does-sql-last-value-parameter-work-in-jdbc-input-plugin/101624/5 "2017-09-26T01:53:33Z")
> [@magnusbaeck](#):
>
> And what query did you end up using?
statement =\> "SELECT \* from table\_name WHERE id \> :sql\_last\_value"
> [@magnusbaeck](#):
>
> Are you sure you started with an empty index?
Yes, I started with an empty index.
> [@magnusbaeck](#):
>
> What does your elasticsearch output configuration look like?
```
elasticsearch {
hosts => " ******"
index => "twiiter"
}
```
---
### Author:  [@magnusbaeck](https://discuss.elastic.co/u/magnusbaeck)
#### Post date: [September 26, 2017, 5:11am UTC](https://discuss.elastic.co/t/how-does-sql-last-value-parameter-work-in-jdbc-input-plugin/101624/6 "2017-09-26T05:11:58Z")
> statement =\> "SELECT \* from table\_name WHERE id \> :sql\_last\_value"
Where's the ORDER BY clause?
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### Author:  [@amruth](https://discuss.elastic.co/u/amruth)
#### Post date: [September 26, 2017, 1:35pm UTC](https://discuss.elastic.co/t/how-does-sql-last-value-parameter-work-in-jdbc-input-plugin/101624/7 "2017-09-26T13:35:16Z")
> [@magnusbaeck](#):
>
> Where's the ORDER BY clause?
statement =\> "SELECT \* from table\_name WHERE id \> :sql\_last\_value ORDER by id"
If I use this statement, will it work correctly? I am assuming it picks the id which is greater than sql\_last\_value and then perform "ORDER by".
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### Author:  [@magnusbaeck](https://discuss.elastic.co/u/magnusbaeck)
#### Post date: [September 26, 2017, 1:41pm UTC](https://discuss.elastic.co/t/how-does-sql-last-value-parameter-work-in-jdbc-input-plugin/101624/8 "2017-09-26T13:41:05Z")
Yes. The highest value will then be processed last, so the next time you run the query it'll ignore all previously seen values.
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### Author:  [@amruth](https://discuss.elastic.co/u/amruth)
#### Post date: [September 26, 2017, 3:55pm UTC](https://discuss.elastic.co/t/how-does-sql-last-value-parameter-work-in-jdbc-input-plugin/101624/9 "2017-09-26T15:55:30Z")
Okay, will try it. Thank you 🙂
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### Author:  [@system](https://discuss.elastic.co/u/system)
#### Post date: [October 24, 2017, 3:55pm UTC](https://discuss.elastic.co/t/how-does-sql-last-value-parameter-work-in-jdbc-input-plugin/101624/10 "2017-10-24T15:55:35Z")
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