AN-140 Metadata index for cost capping

[aednichols]

Description

The cost-capping query below improves from 1m30s to 250ms on the 20M-row test workflow.

select SQL_NO_CACHE
    `WORKFLOW_EXECUTION_UUID`,
    `CALL_FQN`,
    `JOB_SCATTER_INDEX`,
    `JOB_RETRY_ATTEMPT`,
    `METADATA_KEY`,
    `METADATA_VALUE`,
    `METADATA_VALUE_TYPE`,
    `METADATA_TIMESTAMP`,
    `METADATA_JOURNAL_ID`
from
    `METADATA_ENTRY`
where
    (
        (
            `WORKFLOW_EXECUTION_UUID` = '69e8259c-856a-4d87-9cdf-bd709f8e5ce3'
            )
            and (
            (
                (
                    (
                        `METADATA_KEY` like 'vmStartTime%'
                        )
                        or (`METADATA_KEY` like 'vmEndTime%')
                    )
                    or (
                    `METADATA_KEY` like 'vmCostPerHour%'
                    )
                )
                or (
                `METADATA_KEY` like 'subWorkflowId%'
                )
            )
        )
  and (
    (not false)
        or (
        (
            (`CALL_FQN` is null)
                and (`JOB_SCATTER_INDEX` is null)
            )
            and (`JOB_RETRY_ATTEMPT` is null)
        )
    )
order by
    `METADATA_TIMESTAMP`;

This is how Liquibase checks for index existence on MySQL:

SELECT 
  TABLE_CATALOG AS TABLE_CAT, 
  TABLE_SCHEMA AS TABLE_SCHEM, 
  TABLE_NAME, 
  NON_UNIQUE, 
  NULL AS INDEX_QUALIFIER, 
  INDEX_NAME, 
  3 AS TYPE, 
  SEQ_IN_INDEX AS ORDINAL_POSITION, 
  COLUMN_NAME, 
  COLLATION AS ASC_OR_DESC, 
  CARDINALITY, 
  0 AS PAGES, 
  NULL AS FILTER_CONDITION 
FROM 
  INFORMATION_SCHEMA.STATISTICS 
WHERE 
  TABLE_SCHEMA = 'cromwell_test' 
  AND INDEX_NAME = 'IX_METADATA_ENTRY_WEU_MK' 
ORDER BY 
  NON_UNIQUE, 
  INDEX_NAME, 
  SEQ_IN_INDEX

And this is the index create:

CREATE INDEX `IX_METADATA_ENTRY_WEU_MK` ON `cromwell_test`.`METADATA_ENTRY`(
  `WORKFLOW_EXECUTION_UUID`, `METADATA_KEY`
)

A reincarnation of #4736

Release Notes Confirmation

CHANGELOG.md

• I updated CHANGELOG.md in this PR
• I assert that this change shouldn't be included in CHANGELOG.md because it doesn't impact community users

Terra Release Notes

• I added a suggested release notes entry in this Jira ticket
• I assert that this change doesn't need Jira release notes because it doesn't impact Terra users

[salonishah11]

🎉