SQL Practice
SQL 75
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Basics & Filtering Aggregation & Grouping Joins (All Types) Subqueries & Correlated CTEs & Adv. Subqueries Window Functions Advanced & Tricky Schema Design & Opt.
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64. Extract Patients with Multi-Allergies

Medium Apple Advanced & Tricky Problems
Query Rules
  • The query columns and order must match the expected result schema.
  • NULL values should be handled appropriately where applicable.
  • The grader compares output values and sorting order to evaluate.

Schema Browser

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patients
10 cols
doctors
4 cols
admissions
7 cols
province_names
2 cols

Reference Solution

Expected SQL 
SELECT first_name, last_name, allergies FROM patients WHERE (LENGTH(allergies) - LENGTH(REPLACE(allergies, ',', ''))) >= 1;
SQL Editor
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Console Output

Console Terminal

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