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Finding Records Between Tables
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Finding Records Between Tables

MediumSQL · PostgreSQL

Problem

Given two tables, write a query to identify records present in one but not the other using various join types.

Compare records using record_id. Return only records that exist in exactly one table, while preserving the identifying details available from either side.

Output

  1. One row per unmatched record_id
  2. Columns: record_id, table_a_name, table_b_name, and presence
  3. presence must identify whether the record exists only in table_a or only in table_b
  4. Sort by record_id ascending

Schema

table_a
ColumnTypeDescription
record_idPKINTUnique record identifier
record_nameVARCHAR(100)Descriptive record name
statusVARCHAR(30)Current record status
table_b
ColumnTypeDescription
record_idPKINTUnique record identifier
record_nameVARCHAR(100)Descriptive record name
statusVARCHAR(30)Current record status
Tablestable_atable_b
Interviewer

Your question is Finding Records Between Tables. Start with the requirements and the two tables in the Question tab.

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