Major DB schema changes

[vbaranov]

Blockscout DB schema changes for the next major release:

• Eliminate block_index column in internal_transactions table: replace current composite primary key to probably [block_hash, transaction_index, index]
• Drop index token_transfers_from_address_hash_transaction_hash_index (seems to be unsud, see Rewrite query for token transfers on address to eliminate "or" #9576 (comment))
• Drop index token_transfers_to_address_hash_transaction_hash_index index (seems to be unsud, see Rewrite query for token transfers on address to eliminate "or" #9576 (comment))

[k1rill-fedoseev]

Potential logs and token_transfers table optimizations:

• Drop one of logs_block_number_ASC__index_ASC_index, logs_block_number_DESC__index_DESC_index as keeping two of them is redundant. (4% of total table size)
• Drop one of token_transfers_block_number_ASC_log_index_ASC_index, token_transfers_block_number_DESC_log_index_DESC_index as keeping two of them is redundant. (4% of total table size)
• Replace logs_pkey with one of the following:
  • with UNIQUE btree(block_hash, index) (7% of total table size)
  • with UNIQUE btree(transaction_hash, index) AND drop logs_transaction_hash_index_index (20% of total table size)
• Replace token_transfers_pkey with one of the following:
  • with UNIQUE btree(block_hash, log_index) (7% of total table size)
  • with UNIQUE btree(transaction_hash, log_index) AND drop token_transfers_transaction_hash_log_index_index (20% of total table size)