diff --git a/src/blockchain_db/lmdb/db_lmdb.cpp b/src/blockchain_db/lmdb/db_lmdb.cpp
index f9459e8f1..e6d20a9e0 100644
--- a/src/blockchain_db/lmdb/db_lmdb.cpp
+++ b/src/blockchain_db/lmdb/db_lmdb.cpp
@@ -38,6 +38,10 @@
 #include "crypto/crypto.h"
 #include "profile_tools.h"
 
+#if defined(__i386) || defined(__x86_64)
+#define MISALIGNED_OK	1
+#endif
+
 using epee::string_tools::pod_to_hex;
 
 // Increase when the DB changes in a non backward compatible way, and there
@@ -143,22 +147,11 @@ private:
   std::unique_ptr<char[]> data;
 };
 
-auto compare_uint64 = [](const MDB_val *a, const MDB_val *b)
-{
-  const uint64_t va = *(const uint64_t*)a->mv_data;
-  const uint64_t vb = *(const uint64_t*)b->mv_data;
-  if (va < vb) return -1;
-  else if (va == vb) return 0;
-  else return 1;
-};
-
-auto compare_uint8 = [](const MDB_val *a, const MDB_val *b)
+int compare_uint8(const MDB_val *a, const MDB_val *b)
 {
   const uint8_t va = *(const uint8_t*)a->mv_data;
   const uint8_t vb = *(const uint8_t*)b->mv_data;
-  if (va < vb) return -1;
-  else if (va == vb) return 0;
-  else return 1;
+  return va - vb;
 };
 
 int compare_hash32(const MDB_val *a, const MDB_val *b)
@@ -1099,29 +1092,26 @@ void BlockchainLMDB::open(const std::string& filename, const int mdb_flags)
   lmdb_db_open(txn, LMDB_TXS, MDB_CREATE, m_txs, "Failed to open db handle for m_txs");
   lmdb_db_open(txn, LMDB_TX_UNLOCKS, MDB_CREATE, m_tx_unlocks, "Failed to open db handle for m_tx_unlocks");
   lmdb_db_open(txn, LMDB_TX_HEIGHTS, MDB_CREATE, m_tx_heights, "Failed to open db handle for m_tx_heights");
-  lmdb_db_open(txn, LMDB_TX_OUTPUTS, MDB_DUPSORT | MDB_CREATE, m_tx_outputs, "Failed to open db handle for m_tx_outputs");
+  lmdb_db_open(txn, LMDB_TX_OUTPUTS, MDB_DUPSORT | MDB_INTEGERDUP | MDB_CREATE, m_tx_outputs, "Failed to open db handle for m_tx_outputs");
 
   lmdb_db_open(txn, LMDB_OUTPUT_TXS, MDB_INTEGERKEY | MDB_CREATE, m_output_txs, "Failed to open db handle for m_output_txs");
   lmdb_db_open(txn, LMDB_OUTPUT_INDICES, MDB_INTEGERKEY | MDB_CREATE, m_output_indices, "Failed to open db handle for m_output_indices");
-  lmdb_db_open(txn, LMDB_OUTPUT_AMOUNTS, MDB_INTEGERKEY | MDB_DUPSORT | MDB_DUPFIXED | MDB_CREATE, m_output_amounts, "Failed to open db handle for m_output_amounts");
+  lmdb_db_open(txn, LMDB_OUTPUT_AMOUNTS, MDB_INTEGERKEY | MDB_INTEGERDUP| MDB_DUPSORT | MDB_DUPFIXED | MDB_CREATE, m_output_amounts, "Failed to open db handle for m_output_amounts");
   lmdb_db_open(txn, LMDB_OUTPUT_KEYS, MDB_INTEGERKEY | MDB_CREATE, m_output_keys, "Failed to open db handle for m_output_keys");
 
   lmdb_db_open(txn, LMDB_SPENT_KEYS, MDB_CREATE, m_spent_keys, "Failed to open db handle for m_spent_keys");
 
   lmdb_db_open(txn, LMDB_HF_STARTING_HEIGHTS, MDB_CREATE, m_hf_starting_heights, "Failed to open db handle for m_hf_starting_heights");
-  lmdb_db_open(txn, LMDB_HF_VERSIONS, MDB_CREATE, m_hf_versions, "Failed to open db handle for m_hf_versions");
+  lmdb_db_open(txn, LMDB_HF_VERSIONS, MDB_INTEGERKEY| MDB_CREATE, m_hf_versions, "Failed to open db handle for m_hf_versions");
 
   lmdb_db_open(txn, LMDB_PROPERTIES, MDB_CREATE, m_properties, "Failed to open db handle for m_properties");
 
-  mdb_set_dupsort(txn, m_output_amounts, compare_uint64);
-  mdb_set_dupsort(txn, m_tx_outputs, compare_uint64);
   mdb_set_compare(txn, m_spent_keys, compare_hash32);
   mdb_set_compare(txn, m_block_heights, compare_hash32);
   mdb_set_compare(txn, m_txs, compare_hash32);
   mdb_set_compare(txn, m_tx_unlocks, compare_hash32);
   mdb_set_compare(txn, m_tx_heights, compare_hash32);
   mdb_set_compare(txn, m_hf_starting_heights, compare_uint8);
-  mdb_set_compare(txn, m_hf_versions, compare_uint64);
   mdb_set_compare(txn, m_properties, compare_string);
 
   // get and keep current height
@@ -2789,7 +2779,12 @@ uint64_t BlockchainLMDB::get_hard_fork_starting_height(uint8_t version) const
   if (result)
     throw0(DB_ERROR("Error attempting to retrieve a hard fork starting height from the db"));
 
-  uint64_t ret = *(const uint64_t*)val_ret.mv_data;
+  uint64_t ret;
+#ifdef MISALIGNED_OK
+  ret = *(const uint64_t*)val_ret.mv_data;
+#else
+  memcpy(&ret, val_ret.mv_data, sizeof(uint64_t));
+#endif
   TXN_POSTFIX_RDONLY();
   return ret;
 }