Improve sql efficiency for getting the run

[IronPan]

Original query

SELECT
   subq.*,
   CONCAT("[", GROUP_CONCAT(r.Payload SEPARATOR ", "), "]") AS refs 
FROM
   (
      SELECT
         rd.*,
         CONCAT("[", GROUP_CONCAT(m.Payload SEPARATOR ", "), "]") AS metrics 
      FROM
         (
            SELECT
               UUID,
               DisplayName,
               Name,
               StorageState,
               Namespace,
               Description,
               CreatedAtInSec,
               ScheduledAtInSec,
               FinishedAtInSec,
               Conditions,
               PipelineId,
               PipelineSpecManifest,
               WorkflowSpecManifest,
               Parameters,
               pipelineRuntimeManifest,
               WorkflowRuntimeManifest 
            FROM
               run_details
         )
         AS rd 
         LEFT JOIN
            run_metrics AS m 
            ON rd.UUID = m.RunUUID 
      GROUP BY
         rd.UUID
   )
   AS subq 
   LEFT JOIN
      (
         select
            * 
         from
            resource_references 
         where
            ResourceType = 'Run'
      )
      AS r 
      ON subq.UUID = r.ResourceUUID 
WHERE
   UUID = 'a0af02a9-bacb-11e9-a841-42010ad4009a' 
GROUP BY
   subq.UUID LIMIT 1;

This can be improved by moving the where clause to the first select statement.

This change is 

[IronPan]

/assign @hongye-sun

[IronPan]

/retest

[hongye-sun]

/lgtm

[IronPan]

/test kubeflow-pipeline-e2e-test

[IronPan]

/test kubeflow-pipeline-e2e-test

[IronPan]

/approve

[k8s-ci-robot]

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[IronPan]

/test kubeflow-pipeline-e2e-test