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  1. MariaDB Server
  2. MDEV-7853

ORDER BY not working correctly in subquery

        Details

        • Type: Bug
        • Status: Closed
        • Priority: Blocker
        • Resolution: Not a Bug
        • Affects Version/s: 10.0.17, 10.1.3
        • Fix Version/s: N/A
        • Component/s: Data Manipulation - Subquery
        • Labels:
          None
        • Environment:
          10.1.3 - CentOS 6
          10.0.17 - Windows 7

          Description

          This test case

          SELECT
	*
FROM
	(
		SELECT
			*
		FROM
			(
					SELECT
						1 AS agency_id,
						15 AS employee_id
				UNION ALL 
					SELECT
						1 AS agency_id,
						200 AS employee_id
				UNION ALL
					SELECT
						1 AS agency_id,
						688 AS employee_id
				UNION ALL
					SELECT
						2 AS agency_id,
						1 AS employee_id
				UNION ALL 
					SELECT
						2 AS agency_id,
						2 AS employee_id
			) MN
		ORDER BY
			MN.agency_id ASC,
			MN.employee_id DESC
	) T
GROUP BY
	T.agency_id

          ...produce diffrent results comparing to standard MySQL 5.6 edition.

          MySQL 5.6 standard result:
          "1" "688"
          "2" "2"

          MariaDB 10.1.3 / 10.0.17 result:
          "1" "15"
          "2" "1"

          As u can see - data is re-ordered again after leaving subquery, this is potentially very serious bug.

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                serg Sergei Golubchik added a comment -

                It's not a bug, see Why is ORDER BY in a FROM Subquery Ignored?

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                serg Sergei Golubchik added a comment - It's not a bug, see Why is ORDER BY in a FROM Subquery Ignored?

                  People

                  • Assignee:
                    serg Sergei Golubchik
                    Reporter:
                    m.rygiel m.rygiel
                  • Votes:
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                    2 Start watching this issue

                    Dates

                    • Created:
                      Updated:
                      Resolved: