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SQL Top Row Retrieval
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SQL Top Row Retrieval

EasySQL · PostgreSQL

Problem

Write SQL to get the top row of a column.

Assume the top row is the complete row with the highest non-NULL visit_count. If multiple rows share the highest value, return the row with the smallest encounter_id.

Output

  1. Return at most one row with all columns from clinical_encounters.
  2. Exclude rows where visit_count is NULL.
  3. Order the result by highest visit_count, then lowest encounter_id.

Schema

clinical_encounters
ColumnTypeDescription
encounter_idPKINTUnique identifier for the encounter
patient_idINTIdentifier of the patient
provider_nameVARCHAR(100)Name of the assigned provider
encounter_typeVARCHAR(50)Type of clinical encounter
visit_countINTNumber of visits represented by the encounter record
Tablesclinical_encounters
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