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Counting Occurrences in SQL
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Counting Occurrences in SQL

EasySQL · PostgreSQL

Problem

Write a query to count specific occurrences in a dataset.

Count all rows where occurrence_type is exactly ERROR.

Output

  1. Return one row with one column named occurrence_count.
  2. The value must represent only matching rows, including duplicate occurrences.
  3. No ordering is required.

Schema

occurrences
ColumnTypeDescription
occurrence_idPKINTUnique identifier for an occurrence record
occurrence_typeVARCHAR(30)Categorical type assigned to the occurrence
source_systemVARCHAR(40)System that recorded the occurrence
Tablesoccurrences
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