Solutions: Self JOINs

Self JOINs

SELECT we1.id AS we_id,
       we1.account_id AS we1_account_id,
       we1.occurred_at AS we1_occurred_at,
       we1.channel AS we1_channel,
       we2.id AS we2_id,
       we2.account_id AS we2_account_id,
       we2.occurred_at AS we2_occurred_at,
       we2.channel AS we2_channel
  FROM web_events we1 
 LEFT JOIN web_events we2
   ON we1.account_id = we2.account_id
  AND we1.occurred_at > we2.occurred_at
  AND we1.occurred_at <= we2.occurred_at + INTERVAL '1 day'
ORDER BY we1.account_id, we2.occurred_at

Workspace

This section contains either a workspace (it can be a Jupyter Notebook workspace or an online code editor work space, etc.) and it cannot be automatically downloaded to be generated here. Please access the classroom with your account and manually download the workspace to your local machine. Note that for some courses, Udacity upload the workspace files onto https://github.com/udacity, so you may be able to download them there.

Workspace Information:

Default file path:
Workspace type: sql-evaluator
Opened files (when workspace is loaded): n/a

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