Overview
Recently, while writing an SQL query for Solr as a data source in Apache Superset, I encountered a weird issue related to aliasing fields in SQL queries. This post details the problem and the workaround that resolved it.
The Problem
When selecting a field of type UserDefinedType in an SQL query, Superset throws an error.
SELECT
orderId AS `orderId`, -- orderId is of UserDefinedType
itemShippedDate AS `itemShippedDate`
FROM
enterpriseSearch
WHERE
docType = 'OISGIR'
ORDER BY
reservedDatetime;
Running this above query results in an error in the Superset
Solution
After Investigating this issue, We found that when we are using aliases for the selected fields of type UserDefinedType, and assigning the same alias as the name of the actual attribute. Then, the superset will throw an error.
To avoid this kind of issue, a simple ready-to-go solution is not to give the same alias as the attribute name.
Here is the corrected query:
SELECT
orderId AS `order_Id`, -- Using different alias this time
itemShippedDate AS `itemShippedDate`
FROM
enterpriseSearch
WHERE
docType = 'OISGIR'
ORDER BY
reservedDatetime;