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SQL Joins for Test Data
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SQL Joins for Test Data

MediumSQL · PostgreSQL

Problem

Write a SQL query using different types of joins (Inner, Left, Right) to retrieve test data across multiple relational tables.

Use the provided test-management tables and return related suite, case, execution, and environment information. Preserve environments even when no matching test case exists, and preserve test cases when no execution exists.

Output

  1. One row per test execution, test case without an execution, or environment without a test case.
  2. Columns: environment_name, suite_name, test_case_id, test_case_name, run_id, status, and executed_at.
  3. Order by environment, test case, and run, placing missing identifiers last.

Schema

test_suites
ColumnTypeDescription
suite_idPKINTEGERUnique test suite identifier
suite_nameVARCHAR(100)Name of the test suite
test_cases
ColumnTypeDescription
test_case_idPKINTEGERUnique test case identifier
suite_idINTEGERReferenced test suite
environment_idINTEGERReferenced test environment
test_case_nameVARCHAR(150)Test case description
test_runs
ColumnTypeDescription
run_idPKINTEGERUnique test execution identifier
test_case_idINTEGERExecuted test case
statusVARCHAR(20)Execution result
executed_atTIMESTAMPExecution timestamp
test_environments
ColumnTypeDescription
environment_idPKINTEGERUnique test environment identifier
environment_nameVARCHAR(80)Environment or browser name
Tablestest_suitestest_casestest_runstest_environments
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