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SQL MERGE Practice
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SQL MERGE Practice

MediumSQL · PostgreSQL

Problem

Write code to perform a SQL MERGE query.

Asked in the 1st Round Technical Interview stage. SQL coding prompt. Apply the source records to the target records using record_id as the matching key. Matching rows must be updated, and source rows without a target match must be inserted.

Output

  1. The resulting target table, with columns record_id, record_value, status, and updated_at
  2. One row per target record after synchronization
  3. Sort by record_id ascending

Schema

target_records
ColumnTypeDescription
record_idPKINTUnique identifier for the target record
record_valueVARCHAR(100)Current value stored in the target
statusVARCHAR(20)Current processing status
updated_atDATEDate the target record was last updated
source_records
ColumnTypeDescription
record_idPKINTUnique identifier for the incoming record
record_valueVARCHAR(100)Incoming record value
statusVARCHAR(20)Incoming processing status
updated_atDATEDate associated with the incoming record
Tablestarget_recordssource_records
Interviewer

Your question is SQL MERGE Practice. Start with the requirements and the two tables in the Question tab.

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