Required Analyst Competencies

SQL practice question · Easy · Aggregation · LinkedIn

The applicant_skills table lists one skill per row for each candidate (candidate_id, skill); a candidate can appear on several rows and the same skill can be recorded more than once. Return the candidate_id of every candidate who has all three required skills: Python, Tableau and PostgreSQL (exact spelling). Output column: candidate_id. Order by candidate_id ascending.

Table: applicant_skills

Schema of applicant_skills
ColumnType
candidate_idINTEGER
skillTEXT
Sample rows of applicant_skills
candidate_idskill
101Python
101Tableau
101PostgreSQL
102Python
102Tableau
103Python
103Tableau
103PostgreSQL
Expected output on the sample data
candidate_id
101
103

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