Update schema for "tx_outputs" to use array containing amount output indices

This speeds up wallet refresh by directly retrieving a tx's amount output indices.

It removes the indirection and walking the amount output duplicate list
for every amount in each requested tx.

"tx_outputs" is used by:
Amount output indices are needed for wallet refresh.
Global output indices are needed for removing a tx.

Both amount output indices and global output indices are now stored in
an array of 64-bit unsigned ints:

tx_outputs[<tx_hash>] -> [ <a1_oi, a1_gi, a2_oi, a2_gi, ...> ]

Previously it was:
tx_outputs[<tx_hash>] -> duplicate list of <a1_gi, a2_gi, a3_gi, ...>

The amount output list had to be walked for every amount in order to
find each amount's output index, by comparing the amount's global output
index with each one in the duplicate list until a match was found.

See also d045dfa7ce0bf131681193c97560da26f9f37900

1 files changed, 20 insertions, 4 deletions

diff --git a/src/blockchain_db/blockchain_db.h b/src/blockchain_db/blockchain_db.h
index 3396b8c20..2cdaaea6f 100644
--- a/src/blockchain_db/blockchain_db.h
+++ b/src/blockchain_db/blockchain_db.h
@@ -297,7 +297,19 @@ private:
   virtual void remove_transaction_data(const crypto::hash& tx_hash, const transaction& tx) = 0;
 
   // tells the subclass to store an output
-  virtual void add_output(const crypto::hash& tx_hash, const tx_out& tx_output, const uint64_t& local_index, const uint64_t unlock_time) = 0;
+  virtual void add_output(const crypto::hash& tx_hash,
+      const tx_out& tx_output,
+      const uint64_t& local_index,
+      const uint64_t unlock_time,
+      uint64_t& amount_output_index,
+      uint64_t& global_output_index
+      ) = 0;
+
+  // tells the subclass to store indices for a tx's outputs, both amount output indices and global output indices
+  virtual void add_amount_and_global_output_indices(const crypto::hash& tx_hash,
+      const std::vector<uint64_t>& amount_output_indices,
+      const std::vector<uint64_t>& global_output_indices
+      ) = 0;
 
   // tells the subclass to remove an output
   virtual void remove_output(const tx_out& tx_output) = 0;
@@ -501,9 +513,13 @@ public:
 
   virtual bool can_thread_bulk_indices() const = 0;
 
-  // return a vector of indices corresponding to the global output index for
-  // each output in the transaction with hash <h>
-  virtual std::vector<uint64_t> get_tx_output_indices(const crypto::hash& h) const = 0;
+  // return two vectors of indices: vector of amount output indices and global
+  // output indices, corresponding to each output in the transaction with hash
+  // <h>
+  virtual void get_amount_and_global_output_indices(const crypto::hash& h,
+    std::vector<uint64_t>& amount_output_indices,
+    std::vector<uint64_t>& global_output_indices) const = 0;
+
   // return a vector of indices corresponding to the amount output index for
   // each output in the transaction with hash <h>
   virtual std::vector<uint64_t> get_tx_amount_output_indices(const crypto::hash& h) const = 0;