Denormalize action_receipt_actions table in order to improve common queries performance

[frol]

• add columns to action_receipt_actions table and enable indices for them:

  • predecessor_account_id
  • receiver_account_id
  • included_in_block_timestamp

  The motivation is that JOINing with receipts table while doing filtering like receiver_account_id = ? AND action_kind = ? AND args = ? is slow. @vgrichina Could you provide a minimal useful query?

  Ideally, we want to have cross-table indices, but Postgres does not support that, though Postgres 12 and 13 claim to improve various aspects of index performance, so we may want to try to migrate our Postgres 11 database to Postgres 13 to see if that helps.

• add index on args->>'method_name' for FUNCTION_CALL actions (conditional index in Postgres)

• try to decode base64-encoded args->>args_base64 to JSON (replace the original base64 field with args->>args_json if parsing succeeds), so ultimately we will either have args_base64 (e.g. rainbow bridge uses borsh instead of JSON args) or args_json (commonly used by NEAR smart contracts)

  • consider adding indices to args->>'args_json'->>'receiver_id' and args->>'args_json'->>'amount' for FT and NFT

[telezhnaya]

It is also useful to have block_height near block_hash column in all places where applicable (we have block_hash almost everywhere).
It is easier to understand height (compare to timestamp which is unreadable).
I do not insist on it, though.