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Clean Event Statuses for Analysis

EasySQL · PostgreSQL00:00
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Your question is Clean Event Statuses for Analysis. Start with the requirements and the one table on the right.

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Problem

You are given a raw event log exported from Databricks SQL where status values are inconsistent and some rows are not ready for analysis. Write a PostgreSQL query that returns the number of usable events per cleaned status. Treat status values case-insensitively, trim surrounding spaces, exclude rows where the cleaned status is empty or NULL, and only keep rows with a non-NULL event_date. Return the cleaned status and the event count, ordered by event count descending and cleaned status ascending.

Schema

event_log
ColumnTypeDescription
event_idPKINTUnique event identifier
raw_statusVARCHAR(50)Raw status text before cleaning
event_dateDATEDate the event was recorded
source_systemVARCHAR(30)Databricks surface that produced the row
Tablesevent_log
Your solutionPostgreSQL
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