services/horizon: added indexes by id for cb and liquidity pool on tx/ops tables

[sreuland]

PR Checklist

PR Structure

• This PR has reasonably narrow scope (if not, break it down into smaller PRs).
• This PR avoids mixing refactoring changes with feature changes (split into two PRs
  otherwise).
• This PR's title starts with name of package that is most changed in the PR, ex.
  services/friendbot, or all or doc if the changes are broad or impact many
  packages.

Thoroughness

• This PR adds tests for the most critical parts of the new functionality or fixes.
• I've updated any docs (developer docs, .md
  files, etc... affected by this change). Take a look in the docs folder for a given service,
  like this one.

Release planning

• I've updated the relevant CHANGELOG (here for Horizon) if
  needed with deprecations, added features, breaking changes, and DB schema changes.
• I've decided if this PR requires a new major/minor version according to
  semver, or if it's mainly a patch change. The PR is targeted at the next
  release branch if it's not a patch change.

What

added indexes on the cb and liquidity pool id columns in their respective tx/ops materialized join tables

Why

there were slow query performance happening after growth of these tables, and some queries were joining on the id itself which wasn't indexed yet, waiting on long table scans.
Closes #4455
Closes #4436

Known limitations

N/A

[sreuland]

I looked into a few other candidates, history_assets table didn't see need for further indexing, and accounts via history_transaction_participants and history_operation_participants, those tables have a compound index that starts with history_account_id, so, that index can be pulled by query plan in queries by account id.

[bartekn]

LGTM! Do you have any performance stats for this change? Not required, just wonder what's the speed improvements in prd vs stg with mirroring turned on.

[sreuland]

@bartekn , yes, from report on #4455 , /claimable_balances/{cb_id}/transactions, tested on stg, saw response times go from 10+ seconds to sub-second with the indexes in place.

[2opremio]

Any idea of how much do the indices occupy?

[sreuland]

Any idea of how much do the indices occupy?

each index created on stg(with pubnet history from genesis), took about 6GB of size.