apache / apache/druid

V 25.0.0: When using OR condition, giving error : Detected duplicate prefix in join clauses

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Bug
Dominant language
Java
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Description

**Druid Version 25.0.0**

**Query used:**

```
select SUM(fe.dist_total_revenue),
fe.sales_year,
fe.sales_month,
fe.sales_quarter from denorm_fact_extrapolated_unspsc fe
-- INNER join
where fe.manf_desc = 'BDD' OR fe.manf_desc in (SELECT

manf_desc as top5manf_desc
FROM
denorm_fact_extrapolated_unspsc fes
where
__time BETWEEN TIME_PARSE ('2019-01-31T00:00:00.000Z')
AND TIME_PARSE ('2023-01-31T00:00:00.000Z')
AND fes.manf_desc != 'BDD'
and fes.taxonomy_id in (
SELECT
unspsc_code
FROM
denorm_manf_entitlements
where
email_address= 'a@b.com'
)
group by
manf_desc
order by
SUM(fes.dist_total_revenue) desc
limit
5
)

-- top5manf on manf_desc = top5manf_desc
-- WHERE
AND __time BETWEEN TIME_PARSE ('2019-01-31T00:00:00.000Z')
AND TIME_PARSE ('2023-01-31T00:00:00.000Z')
AND fe.taxonomy_id IN(
SELECT
unspsc_code
FROM
denorm_manf_entitlements
WHERE
email_address= 'a@b.com'
)
group by fe.sales_year,
fe.sales_month,
fe.sales_quarter
```

**Error when running above code:**

> Error: Unknown exception
> Detected duplicate prefix in join clauses: [__j0.]
> org.apache.druid.java.util.common.IAE

**Main Issue**

If i remove below code from the query, it works

```
OR fe.manf_desc in (SELECT 

                      manf_desc as top5manf_desc 
                    FROM 
                      denorm_fact_extrapolated_unspsc fes 
                    where 
                      __time BETWEEN TIME_PARSE ('2019-01-31T00:00:00.000Z') 
                      AND TIME_PARSE ('2023-01-31T00:00:00.000Z')
                      AND fes.manf_desc != 'BDD'
                      and fes.taxonomy_id in (
                        SELECT 
                          unspsc_code 
                        FROM 
                          denorm_manf_entitlements 
                        where 
                          email_address= 'a@b.com'
                      )
                    group by 
                      manf_desc
                    order by 
                      SUM(fes.dist_total_revenue) desc 
                    limit 
                      5
                      )
```

Contributor guide

Open the contributing guide

Research direction

Start by reproducing the supplied query against Apache Druid 25.0.0 and confirm the “Detected duplicate prefix in join clauses: [__j0.]” error. Compare it with the query after removing the OR subquery; done means the complete query no longer raises the duplicate-prefix exception and regression coverage demonstrates the case.

Written by the indexing model from the issue text.

Assessment

Tech stack
java, sql
Domain
databases
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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