Question

Merge Queries & Row Limits - a word of warning

  • 6 December 2019
  • 7 replies
  • 1052 views

Userlevel 2

A word of warning around merge queries that we’ve just discovered, but is not made clear in the documentation:


When two queries are merged, the first 5000 rows are taken from each query and merged, regardless of what row limits you set in each query individually. So if you have a queries with potential results larger than 5000 rows, merge queries are not advised.


For example, if you were looking to merge a query of customer ID and order count, with a query of customer ID and complaint count, if your top ordering customer was the 5001th most frequent complainer, you would just see null for complaint count.


As such merge queries should be used with extreme caution with larger datasets to avoid misleading results


7 replies

Workaround is to filter in downstream (non-primary) explores on the same filters as in primary (only helpful if this gets you under the row limit of course)

Userlevel 2
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Hi, I’ve created a feature request here, if you want to vote: Remove row limit on merges

Userlevel 1

+1 merge query is severely limited because of this. Also, the ability to set a row limit on the merged query would be useful

+1

A huge blocker in many situations.

Userlevel 5
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+1 for updates on this.

Has anyone found a workaround? Even with the Download without Limit option it seems like the merged queries will still only pull the first 5000 records when downloading the csv.

Thanks @Kat_Lee. We encountered a similar challenge recently where we had to flag our top 100 customers for yearly report segregated by months. We ended up using merge query and reporting wrong numbers.

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