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Top 10 Most Frequent Items
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Top 10 Most Frequent Items

MediumSQL · PostgreSQL

Problem

Write a SQL query to find the top 10 most frequent items in a dataset.

Use item_events as the occurrence dataset and item_catalog for item names. Return up to 10 items that exist in the catalog and have at least one event.

Output

  1. One row per item with columns item_id, item_name, and frequency
  2. Sort by frequency descending, then item_name ascending, then item_id ascending to break ties

Schema

item_events
ColumnTypeDescription
event_idPKINTUnique occurrence record identifier
item_idINTItem associated with the occurrence
item_catalog
ColumnTypeDescription
item_idPKINTUnique item identifier
item_nameVARCHAR(100)Display name of the item
Tablesitem_eventsitem_catalog
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Your question is Top 10 Most Frequent Items. Start with the requirements and the two tables in the Question tab.

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