Find patients who have Type I Diabetes. Condition codes start with 'DIAB1'. Return patient_id and name.
This challenge now meets the current minimum standard for sitemap inclusion and independent indexing.
Find patients who have Type I Diabetes. Condition codes start with 'DIAB1'. Return patient_id and name.
String filtering problems like this come up constantly in healthcare, compliance, CRM tagging, and messy operational systems where multiple codes are packed into one text field. The real skill is writing pattern logic that matches the intended token without accidentally matching nearby strings.
patient_idnameconditionsSELECT
patient_id,
name
FROM patients
WHERE conditions LIKE 'DIAB1%'
OR conditions LIKE '% DIAB1%'This solution works because valid matches appear either at the start of the string or immediately after a space. It is compact and fits the simplified schema in this challenge.
SELECT
patient_id,
name
FROM patients
WHERE ' ' || conditions || ' ' LIKE '% DIAB1%'Padding the value with spaces normalizes the matching rule into one pattern. This reduces the chance of forgetting to handle the start-of-string case separately.
The main bug is using `LIKE '%DIAB1%'`, which would also match codes such as `XDIAB100` if token boundaries were not respected. Another issue is forgetting that the condition code may appear at the very beginning of the string, not only in the middle.
Because the problem is not just substring matching. You want a condition code that starts with `DIAB1` as its own code token, not any arbitrary string fragment buried inside another value.
It teaches defensive string filtering on denormalized fields. In real datasets, codes are often packed into one column, so matching logic needs to account for separators and false positives.
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