major rework of withdraw transaction to use stored procedure and (presumably) reduce serialization failures by avoiding SELECT before INSERT

5 files changed, 420 insertions, 136 deletions

diff --git a/src/exchangedb/.gitignore b/src/exchangedb/.gitignore
index 830cf10c..aea9a74e 100644
--- a/src/exchangedb/.gitignore
+++ b/src/exchangedb/.gitignore
@@ -4,3 +4,4 @@ test-exchangedb-fees
 test-exchangedb-postgres
 test-exchangedb-signkeys
 test-perf-taler-exchangedb
+bench-db-postgres
diff --git a/src/exchangedb/drop0001.sql b/src/exchangedb/drop0001.sql
index 52079e52..3dcbb81f 100644
--- a/src/exchangedb/drop0001.sql
+++ b/src/exchangedb/drop0001.sql
@@ -54,6 +54,10 @@ DROP TABLE IF EXISTS reserves CASCADE;
 DROP TABLE IF EXISTS denomination_revocations CASCADE;
 DROP TABLE IF EXISTS denominations CASCADE;
 
+DROP FUNCTION IF EXISTS exchange_do_withdraw(bigint,integer,bytea,bytea,bytea,bytea,bytea,bigint,bigint) ;
+
+DROP FUNCTION IF EXISTS exchange_do_withdraw_limit_check(bigint,bigint,bigint,int) ;
+
 
 -- And we're out of here...
 COMMIT;
diff --git a/src/exchangedb/exchange-0001.sql b/src/exchangedb/exchange-0001.sql
index 7acd6724..80ad9527 100644
--- a/src/exchangedb/exchange-0001.sql
+++ b/src/exchangedb/exchange-0001.sql
@@ -680,6 +680,211 @@ CREATE INDEX IF NOT EXISTS revolving_work_shards_index
   );
 
 
+-- Stored procedures
+
+
+DROP FUNCTION IF EXISTS exchange_do_withdraw(bigint,integer,bytea,bytea,bytea,bytea,bytea,bigint,bigint) ;
+
+CREATE OR REPLACE FUNCTION exchange_do_withdraw(
+  IN amount_val INT8,
+  IN amount_frac INT4,
+  IN h_denom_pub BYTEA,
+  IN rpub BYTEA,
+  IN reserve_sig BYTEA,
+  IN h_coin_envelope BYTEA,
+  IN denom_sig BYTEA,
+  IN now INT8,
+  IN min_reserve_gc INT8,
+  OUT reserve_found BOOLEAN,
+  OUT balance_ok BOOLEAN,
+  OUT kycok BOOLEAN,
+  OUT ruuid INT8,
+  OUT account_uuid INT8)
+LANGUAGE plpgsql
+AS $$
+DECLARE
+  reserve_gc INT8;
+DECLARE
+  denom_serial INT8;
+DECLARE
+  reserve_val INT8;
+DECLARE
+  reserve_frac INT4;
+BEGIN
+
+SELECT denominations_serial INTO denom_serial
+  FROM denominations
+ WHERE denom_pub_hash=h_denom_pub;
+
+IF NOT FOUND
+THEN
+  -- denomination unknown, should be impossible!
+  reserve_found=FALSE;
+  balance_ok=FALSE;
+  kycok=FALSE;
+  ruuid=0;
+  account_uuid=0;
+  ASSERT false, 'denomination unknown';
+  RETURN;
+END IF;
+
+SELECT
+   reserves.reserve_uuid
+  ,current_balance_val
+  ,current_balance_frac
+  ,expiration_date
+  ,gc_date
+ INTO
+   ruuid
+  ,reserve_val
+  ,reserve_frac
+  ,reserve_gc
+  FROM reserves
+ WHERE reserves.reserve_pub=rpub;
+
+IF NOT FOUND
+THEN
+  -- reserve unknown
+  reserve_found=FALSE;
+  balance_ok=FALSE;
+  kycok=FALSE;
+  account_uuid=0;
+  RETURN;
+END IF;
+
+-- We optimistically insert, and then on conflict declare
+-- the query successful due to idempotency.
+INSERT INTO reserves_out
+  (h_blind_ev
+  ,denominations_serial
+  ,denom_sig
+  ,reserve_uuid
+  ,reserve_sig
+  ,execution_date
+  ,amount_with_fee_val
+  ,amount_with_fee_frac)
+VALUES
+  (h_coin_envelope
+  ,denom_serial
+  ,denom_sig
+  ,ruuid
+  ,reserve_sig
+  ,now
+  ,amount_val
+  ,amount_frac)
+ON CONFLICT DO NOTHING;
+
+IF NOT FOUND
+THEN
+  -- idempotent query, all constraints must be satisfied
+  reserve_found=TRUE;
+  balance_ok=TRUE;
+  kycok=TRUE;
+  account_uuid=0;
+  RETURN;
+END IF;
+
+-- Check reserve balance is sufficient.
+IF (reserve_val > amount_val)
+THEN
+  IF (reserve_frac > amount_frac)
+  THEN
+    reserve_val=reserve_val - amount_val;
+    reserve_frac=reserve_frac - amount_frac;
+  ELSE
+    reserve_val=reserve_val - amount_val - 1;
+    reserve_frac=reserve_frac + 100000000 - amount_frac;
+  END IF;
+ELSE
+  IF (reserve_val = amount_val) AND (reserve_frac >= amount_frac)
+  THEN
+    reserve_val=0;
+    reserve_frac=reserve_frac - amount_frac;
+  ELSE
+    reserve_found=TRUE;
+    balance_ok=FALSE;
+    kycok=FALSE; -- we do not really know or care
+    account_uuid=0;
+    RETURN;
+  END IF;
+END IF;
+
+-- Calculate new expiration dates.
+min_reserve_gc=GREATEST(min_reserve_gc,reserve_gc);
+
+-- Update reserve balance.
+UPDATE reserves SET
+  gc_date=min_reserve_gc
+ ,current_balance_val=reserve_val
+ ,current_balance_frac=reserve_frac
+WHERE
+  reserves.reserve_uuid=ruuid;
+
+reserve_found=TRUE;
+balance_ok=TRUE;
+
+-- Obtain KYC status based on the last wire transfer into
+-- this reserve. FIXME: likely not adequate for reserves that got P2P transfers!
+SELECT
+   kyc_ok
+  ,wire_source_serial_id
+  INTO
+   kycok
+  ,account_uuid
+  FROM reserves_in
+  JOIN wire_targets ON (wire_source_serial_id = wire_target_serial_id)
+ WHERE reserve_uuid=ruuid
+ LIMIT 1; -- limit 1 should not be required (without p2p transfers)
+
+END $$;
+
+COMMENT ON FUNCTION exchange_do_withdraw(INT8, INT4, BYTEA, BYTEA, BYTEA, BYTEA, BYTEA, INT8, INT8)
+  IS 'Checks whether the reserve has sufficient balance for a withdraw operation (or the request is repeated and was previously approved) and if so updates the database with the result';
+
+
+
+DROP FUNCTION IF EXISTS exchange_do_withdraw_limit_check(bigint,bigint,bigint,int) ;
+
+
+CREATE OR REPLACE FUNCTION exchange_do_withdraw_limit_check(
+  IN ruuid INT8,
+  IN start_time INT8,
+  IN upper_limit_val INT8,
+  IN upper_limit_frac INT4,
+  OUT below_limit BOOLEAN)
+LANGUAGE plpgsql
+AS $$
+DECLARE
+  total_val INT8;
+DECLARE
+  total_frac INT8; -- INT4 could overflow during accumulation!
+BEGIN
+
+SELECT
+   SUM(amount_with_fee_val) -- overflow here is not plausible
+  ,SUM(CAST(amount_with_fee_frac AS INT8)) -- compute using 64 bits
+  INTO
+   total_val
+  ,total_frac
+  FROM reserves_out
+ WHERE reserves_out.reserve_uuid=ruuid
+   AND execution_date > start_time;
+
+-- normalize result
+total_val = total_val + total_frac / 100000000;
+total_frac = total_frac % 100000000;
+
+-- compare to threshold
+below_limit = (total_val < upper_limit_val) OR
+            ( (total_val = upper_limit_val) AND
+              (total_frac <= upper_limit_frac) );
+END $$;
+
+COMMENT ON FUNCTION exchange_do_withdraw_limit_check(INT8, INT8, INT8, INT4)
+  IS 'Check whether the withdrawals from the given reserve since the given time are below the given threshold';
+
+
+
 
 
 -- Complete transaction
diff --git a/src/exchangedb/plugin_exchangedb_postgres.c b/src/exchangedb/plugin_exchangedb_postgres.c
index 004516c5..9bdac759 100644
--- a/src/exchangedb/plugin_exchangedb_postgres.c
+++ b/src/exchangedb/plugin_exchangedb_postgres.c
@@ -596,6 +596,34 @@ prepare_statements (struct PostgresClosure *pg)
       "lock_withdraw",
       "LOCK TABLE reserves_out;",
       0),
+    /* Used in #postgres_do_withdraw() to store
+       the signature of a blinded coin with the blinded coin's
+       details before returning it during /reserve/withdraw. We store
+       the coin's denomination information (public key, signature)
+       and the blinded message as well as the reserve that the coin
+       is being withdrawn from and the signature of the message
+       authorizing the withdrawal. */
+    GNUNET_PQ_make_prepare (
+      "call_withdraw",
+      "SELECT "
+      " reserve_found"
+      ",balance_ok"
+      ",kycok AS kyc_ok"
+      ",ruuid AS reserve_uuid"
+      ",account_uuid AS payment_target_uuid"
+      " FROM exchange_do_withdraw"
+      " ($1,$2,$3,$4,$5,$6,$7,$8,$9);",
+      9),
+    /* Used in #postgres_do_withdraw_limit_check() to check
+       if the withdrawals remain below the limit under which
+       KYC is not required. */
+    GNUNET_PQ_make_prepare (
+      "call_withdraw_limit_check",
+      "SELECT "
+      " below_limit"
+      " FROM exchange_do_withdraw_limit_check"
+      " ($1,$2,$3,$4);",
+      4),
     /* Used in #postgres_insert_withdraw_info() to store
        the signature of a blinded coin with the blinded coin's
        details before returning it during /reserve/withdraw. We store
@@ -3378,12 +3406,12 @@ dominations_cb_helper (void *cls,
     struct TALER_DenominationPublicKey denom_pub;
     struct TALER_MasterSignatureP master_sig;
     struct TALER_DenominationHash h_denom_pub;
-    uint8_t revoked;
+    bool revoked;
     struct GNUNET_PQ_ResultSpec rs[] = {
       GNUNET_PQ_result_spec_auto_from_type ("master_sig",
                                             &master_sig),
-      GNUNET_PQ_result_spec_auto_from_type ("revoked",
-                                            &revoked),
+      GNUNET_PQ_result_spec_bool ("revoked",
+                                  &revoked),
       TALER_PQ_result_spec_absolute_time ("valid_from",
                                           &meta.start),
       TALER_PQ_result_spec_absolute_time ("expire_withdraw",
@@ -3422,7 +3450,7 @@ dominations_cb_helper (void *cls,
              &h_denom_pub,
              &meta,
              &master_sig,
-             (0 != revoked));
+             revoked);
     GNUNET_PQ_cleanup_result (rs);
   }
 }
@@ -3777,7 +3805,6 @@ postgres_reserves_get (void *cls,
     GNUNET_PQ_query_param_auto_from_type (&reserve->pub),
     GNUNET_PQ_query_param_end
   };
-  uint8_t ok8;
   struct GNUNET_PQ_ResultSpec rs[] = {
     TALER_PQ_RESULT_SPEC_AMOUNT ("current_balance",
                                  &reserve->balance),
@@ -3787,19 +3814,16 @@ postgres_reserves_get (void *cls,
                                         &reserve->gc),
     GNUNET_PQ_result_spec_uint64 ("payment_target_uuid",
                                   &kyc->payment_target_uuid),
-    GNUNET_PQ_result_spec_auto_from_type ("kyc_ok",
-                                          &ok8),
+    GNUNET_PQ_result_spec_bool ("kyc_ok",
+                                &kyc->ok),
     GNUNET_PQ_result_spec_end
   };
-  enum GNUNET_DB_QueryStatus qs;
 
-  qs = GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
-                                                 "reserves_get_with_kyc",
-                                                 params,
-                                                 rs);
   kyc->type = TALER_EXCHANGEDB_KYC_WITHDRAW;
-  kyc->ok = (0 != ok8);
-  return qs;
+  return GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
+                                                   "reserves_get_with_kyc",
+                                                   params,
+                                                   rs);
 }
 
 
@@ -3874,23 +3898,19 @@ postgres_get_kyc_status (void *cls,
     GNUNET_PQ_query_param_string (payto_uri),
     GNUNET_PQ_query_param_end
   };
-  uint8_t ok8;
   struct GNUNET_PQ_ResultSpec rs[] = {
     GNUNET_PQ_result_spec_uint64 ("payment_target_uuid",
                                   &kyc->payment_target_uuid),
     GNUNET_PQ_result_spec_auto_from_type ("kyc_ok",
-                                          &ok8),
+                                          &kyc->ok),
     GNUNET_PQ_result_spec_end
   };
-  enum GNUNET_DB_QueryStatus qs;
 
-  qs = GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
-                                                 "get_kyc_status",
-                                                 params,
-                                                 rs);
   kyc->type = TALER_EXCHANGEDB_KYC_DEPOSIT;
-  kyc->ok = (0 != ok8);
-  return qs;
+  return GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
+                                                   "get_kyc_status",
+                                                   params,
+                                                   rs);
 }
 
 
@@ -3914,24 +3934,20 @@ postgres_select_kyc_status (void *cls,
     GNUNET_PQ_query_param_uint64 (&payment_target_uuid),
     GNUNET_PQ_query_param_end
   };
-  uint8_t ok8;
   struct GNUNET_PQ_ResultSpec rs[] = {
     GNUNET_PQ_result_spec_auto_from_type ("h_payto",
                                           h_payto),
     GNUNET_PQ_result_spec_auto_from_type ("kyc_ok",
-                                          &ok8),
+                                          &kyc->ok),
     GNUNET_PQ_result_spec_end
   };
-  enum GNUNET_DB_QueryStatus qs;
 
-  qs = GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
-                                                 "select_kyc_status",
-                                                 params,
-                                                 rs);
   kyc->type = TALER_EXCHANGEDB_KYC_UNKNOWN;
-  kyc->ok = (0 != ok8);
   kyc->payment_target_uuid = payment_target_uuid;
-  return qs;
+  return GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
+                                                   "select_kyc_status",
+                                                   params,
+                                                   rs);
 }
 
 
@@ -3962,12 +3978,11 @@ inselect_account_kyc_status (
       GNUNET_PQ_query_param_auto_from_type (&h_payto),
       GNUNET_PQ_query_param_end
     };
-    uint8_t ok8 = 0;
     struct GNUNET_PQ_ResultSpec rs[] = {
       GNUNET_PQ_result_spec_uint64 ("wire_target_serial_id",
                                     &kyc->payment_target_uuid),
-      GNUNET_PQ_result_spec_auto_from_type ("kyc_ok",
-                                            &ok8),
+      GNUNET_PQ_result_spec_bool ("kyc_ok",
+                                  &kyc->ok),
       GNUNET_PQ_result_spec_end
     };
 
@@ -3998,10 +4013,6 @@ inselect_account_kyc_status (
         return GNUNET_DB_STATUS_SOFT_ERROR;
       kyc->ok = false;
     }
-    else
-    {
-      kyc->ok = (0 != ok8);
-    }
   }
   kyc->type = TALER_EXCHANGEDB_KYC_BALANCE;
   return qs;
@@ -4478,86 +4489,104 @@ postgres_get_withdraw_info (
 
 
 /**
- * Store collectable bit coin under the corresponding
- * hash of the blinded message.
+ * Perform withdraw operation, checking for sufficient balance
+ * and possibly persisting the withdrawal details.
  *
  * @param cls the `struct PostgresClosure` with the plugin-specific state
  * @param collectable corresponding collectable coin (blind signature)
  *                    if a coin is found
+ * @param now current time (rounded)
+ * @param[out] found set to true if the reserve was found
+ * @param[out] balance_ok set to true if the balance was sufficient
+ * @param[out] kyc_ok set to true if the kyc status of the reserve is satisfied
+ * @param[out] reserve_uuid set to the UUID of the reserve
  * @return query execution status
  */
 static enum GNUNET_DB_QueryStatus
-postgres_insert_withdraw_info (
+postgres_do_withdraw (
   void *cls,
-  const struct TALER_EXCHANGEDB_CollectableBlindcoin *collectable)
+  const struct TALER_EXCHANGEDB_CollectableBlindcoin *collectable,
+  struct GNUNET_TIME_Absolute now,
+  bool *found,
+  bool *balance_ok,
+  struct TALER_EXCHANGEDB_KycStatus *kyc,
+  uint64_t *reserve_uuid)
 {
   struct PostgresClosure *pg = cls;
-  struct TALER_EXCHANGEDB_Reserve reserve;
-  struct GNUNET_TIME_Absolute now;
   struct GNUNET_TIME_Absolute gc;
   struct GNUNET_PQ_QueryParam params[] = {
-    GNUNET_PQ_query_param_auto_from_type (&collectable->h_coin_envelope),
+    TALER_PQ_query_param_amount (&collectable->amount_with_fee),
     GNUNET_PQ_query_param_auto_from_type (&collectable->denom_pub_hash),
-    TALER_PQ_query_param_blinded_denom_sig (&collectable->sig),
     GNUNET_PQ_query_param_auto_from_type (&collectable->reserve_pub),
     GNUNET_PQ_query_param_auto_from_type (&collectable->reserve_sig),
+    GNUNET_PQ_query_param_auto_from_type (&collectable->h_coin_envelope),
+    TALER_PQ_query_param_blinded_denom_sig (&collectable->sig),
     TALER_PQ_query_param_absolute_time (&now),
-    TALER_PQ_query_param_amount (&collectable->amount_with_fee),
+    TALER_PQ_query_param_absolute_time (&gc),
     GNUNET_PQ_query_param_end
   };
-  enum GNUNET_DB_QueryStatus qs;
-
-  now = GNUNET_TIME_absolute_get ();
-  (void) GNUNET_TIME_round_abs (&now);
-  qs = GNUNET_PQ_eval_prepared_non_select (pg->conn,
-                                           "insert_withdraw_info",
-                                           params);
-  if (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT != qs)
-  {
-    GNUNET_break (GNUNET_DB_STATUS_SOFT_ERROR == qs);
-    return qs;
-  }
+  struct GNUNET_PQ_ResultSpec rs[] = {
+    GNUNET_PQ_result_spec_bool ("reserve_found",
+                                found),
+    GNUNET_PQ_result_spec_bool ("balance_ok",
+                                balance_ok),
+    GNUNET_PQ_result_spec_bool ("kyc_ok",
+                                &kyc->ok),
+    GNUNET_PQ_result_spec_uint64 ("reserve_uuid",
+                                  reserve_uuid),
+    GNUNET_PQ_result_spec_uint64 ("payment_target_uuid",
+                                  &kyc->payment_target_uuid),
+    GNUNET_PQ_result_spec_end
+  };
 
-  /* update reserve balance */
-  reserve.pub = collectable->reserve_pub;
-  if (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT !=
-      (qs = reserves_get_internal (pg,
-                                   &reserve)))
-  {
-    /* Should have been checked before we got here... */
-    GNUNET_break (GNUNET_DB_STATUS_SOFT_ERROR == qs);
-    if (GNUNET_DB_STATUS_SUCCESS_NO_RESULTS == qs)
-      qs = GNUNET_DB_STATUS_HARD_ERROR;
-    return qs;
-  }
-  if (0 >
-      TALER_amount_subtract (&reserve.balance,
-                             &reserve.balance,
-                             &collectable->amount_with_fee))
-  {
-    /* The reserve history was checked to make sure there is enough of a balance
-       left before we tried this; however, concurrent operations may have changed
-       the situation by now, causing us to fail here. As reserves can no longer
-       be topped up, retrying should not help either.  */
-    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-                "Withdrawal from reserve `%s' refused due to insufficient balance.\n",
-                TALER_B2S (&collectable->reserve_pub));
-    return GNUNET_DB_STATUS_HARD_ERROR;
-  }
   gc = GNUNET_TIME_absolute_add (now,
                                  pg->legal_reserve_expiration_time);
-  reserve.gc = GNUNET_TIME_absolute_max (gc,
-                                         reserve.gc);
-  (void) GNUNET_TIME_round_abs (&reserve.gc);
-  qs = reserves_update (pg,
-                        &reserve);
-  GNUNET_break (GNUNET_DB_STATUS_HARD_ERROR != qs);
-  if (GNUNET_DB_STATUS_SUCCESS_NO_RESULTS == qs)
-  {
-    GNUNET_break (0);
-    qs = GNUNET_DB_STATUS_HARD_ERROR;
-  }
-  return qs;
+  (void) GNUNET_TIME_round_abs (&gc);
+  kyc->type = TALER_EXCHANGEDB_KYC_WITHDRAW;
+  return GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
+                                                   "call_withdraw",
+                                                   params,
+                                                   rs);
+
+}
+
+
+/**
+ * Check that reserve remains below threshold for KYC
+ * checks after withdraw operation.
+ *
+ * @param cls the `struct PostgresClosure` with the plugin-specific state
+ * @param reserve_uuid reserve to check
+ * @param withdraw_start starting point to accumulate from
+ * @param upper_limit maximum amount allowed
+ * @param[out] below_limit set to true if the limit was not exceeded
+ * @return query execution status
+ */
+static enum GNUNET_DB_QueryStatus
+postgres_do_withdraw_limit_check (
+  void *cls,
+  uint64_t reserve_uuid,
+  struct GNUNET_TIME_Absolute withdraw_start,
+  const struct TALER_Amount *upper_limit,
+  bool *below_limit)
+{
+  struct PostgresClosure *pg = cls;
+  struct GNUNET_PQ_QueryParam params[] = {
+    GNUNET_PQ_query_param_uint64 (&reserve_uuid),
+    TALER_PQ_query_param_absolute_time (&withdraw_start),
+    TALER_PQ_query_param_amount (upper_limit),
+    GNUNET_PQ_query_param_end
+  };
+  struct GNUNET_PQ_ResultSpec rs[] = {
+    GNUNET_PQ_result_spec_bool ("below_limit",
+                                below_limit),
+    GNUNET_PQ_result_spec_end
+  };
+
+  return GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
+                                                   "call_withdraw_limit_check",
+                                                   params,
+                                                   rs);
 }
 
 
@@ -4588,10 +4617,20 @@ struct ReserveHistoryContext
   struct PostgresClosure *pg;
 
   /**
+   * Sum of all credit transactions.
+   */
+  struct TALER_Amount balance_in;
+
+  /**
+   * Sum of all debit transactions.
+   */
+  struct TALER_Amount balance_out;
+
+  /**
    * Set to #GNUNET_SYSERR on serious internal errors during
    * the callbacks.
    */
-  int status;
+  enum GNUNET_GenericReturnValue status;
 };
 
 
@@ -4667,6 +4706,10 @@ add_bank_to_exchange (void *cls,
         return;
       }
     }
+    GNUNET_assert (0 <=
+                   TALER_amount_add (&rhc->balance_in,
+                                     &rhc->balance_in,
+                                     &bt->amount));
     bt->reserve_pub = *rhc->reserve_pub;
     tail = append_rh (rhc);
     tail->type = TALER_EXCHANGEDB_RO_BANK_TO_EXCHANGE;
@@ -4724,6 +4767,10 @@ add_withdraw_coin (void *cls,
         return;
       }
     }
+    GNUNET_assert (0 <=
+                   TALER_amount_add (&rhc->balance_out,
+                                     &rhc->balance_out,
+                                     &cbc->amount_with_fee));
     cbc->reserve_pub = *rhc->reserve_pub;
     tail = append_rh (rhc);
     tail->type = TALER_EXCHANGEDB_RO_WITHDRAW_COIN;
@@ -4784,6 +4831,10 @@ add_recoup (void *cls,
         return;
       }
     }
+    GNUNET_assert (0 <=
+                   TALER_amount_add (&rhc->balance_in,
+                                     &rhc->balance_in,
+                                     &recoup->value));
     recoup->reserve_pub = *rhc->reserve_pub;
     tail = append_rh (rhc);
     tail->type = TALER_EXCHANGEDB_RO_RECOUP_COIN;
@@ -4840,6 +4891,10 @@ add_exchange_to_bank (void *cls,
         return;
       }
     }
+    GNUNET_assert (0 <=
+                   TALER_amount_add (&rhc->balance_out,
+                                     &rhc->balance_out,
+                                     &closing->amount));
     closing->reserve_pub = *rhc->reserve_pub;
     tail = append_rh (rhc);
     tail->type = TALER_EXCHANGEDB_RO_EXCHANGE_TO_BANK;
@@ -4854,12 +4909,14 @@ add_exchange_to_bank (void *cls,
  *
  * @param cls the `struct PostgresClosure` with the plugin-specific state
  * @param reserve_pub public key of the reserve
+ * @param[out] balance set to the reserve balance
  * @param[out] rhp set to known transaction history (NULL if reserve is unknown)
  * @return transaction status
  */
 static enum GNUNET_DB_QueryStatus
 postgres_get_reserve_history (void *cls,
                               const struct TALER_ReservePublicKeyP *reserve_pub,
+                              struct TALER_Amount *balance,
                               struct TALER_EXCHANGEDB_ReserveHistory **rhp)
 {
   struct PostgresClosure *pg = cls;
@@ -4902,6 +4959,12 @@ postgres_get_reserve_history (void *cls,
   rhc.rh_tail = NULL;
   rhc.pg = pg;
   rhc.status = GNUNET_OK;
+  GNUNET_assert (GNUNET_OK ==
+                 TALER_amount_set_zero (pg->currency,
+                                        &rhc.balance_in));
+  GNUNET_assert (GNUNET_OK ==
+                 TALER_amount_set_zero (pg->currency,
+                                        &rhc.balance_out));
   qs = GNUNET_DB_STATUS_SUCCESS_NO_RESULTS; /* make static analysis happy */
   for (unsigned int i = 0; NULL != work[i].cb; i++)
   {
@@ -4927,6 +4990,10 @@ postgres_get_reserve_history (void *cls,
     }
   }
   *rhp = rhc.rh;
+  GNUNET_assert (0 <=
+                 TALER_amount_subtract (balance,
+                                        &rhc.balance_in,
+                                        &rhc.balance_out));
   return qs;
 }
 
@@ -5308,13 +5375,12 @@ postgres_get_ready_deposit (void *cls,
                             void *deposit_cb_cls)
 {
   struct PostgresClosure *pg = cls;
-  uint8_t kyc_override = (kyc_off) ? 1 : 0;
   struct GNUNET_TIME_Absolute now = GNUNET_TIME_absolute_get ();
   struct GNUNET_PQ_QueryParam params[] = {
     TALER_PQ_query_param_absolute_time (&now),
     GNUNET_PQ_query_param_uint64 (&start_shard_row),
     GNUNET_PQ_query_param_uint64 (&end_shard_row),
-    GNUNET_PQ_query_param_auto_from_type (&kyc_override),
+    GNUNET_PQ_query_param_bool (kyc_off),
     GNUNET_PQ_query_param_end
   };
   struct TALER_Amount amount_with_fee;
@@ -6609,7 +6675,6 @@ add_coin_deposit (void *cls,
     chc->have_deposit_or_melt = true;
     deposit = GNUNET_new (struct TALER_EXCHANGEDB_DepositListEntry);
     {
-      uint8_t done = 0;
       struct GNUNET_PQ_ResultSpec rs[] = {
         TALER_PQ_RESULT_SPEC_AMOUNT ("amount_with_fee",
                                      &deposit->amount_with_fee),
@@ -6636,7 +6701,7 @@ add_coin_deposit (void *cls,
         GNUNET_PQ_result_spec_uint64 ("deposit_serial_id",
                                       &serial_id),
         GNUNET_PQ_result_spec_auto_from_type ("done",
-                                              &done),
+                                              &deposit->done),
         GNUNET_PQ_result_spec_end
       };
 
@@ -6650,7 +6715,6 @@ add_coin_deposit (void *cls,
         chc->failed = true;
         return;
       }
-      deposit->done = (0 != done);
     }
     tl = GNUNET_new (struct TALER_EXCHANGEDB_TransactionList);
     tl->next = chc->head;
@@ -7340,7 +7404,6 @@ postgres_lookup_transfer_by_deposit (
     /* Check if transaction exists in deposits, so that we just
        do not have a WTID yet. In that case, return without wtid
        (by setting 'pending' true). */
-    uint8_t ok8 = 0;
     struct GNUNET_PQ_ResultSpec rs2[] = {
       GNUNET_PQ_result_spec_auto_from_type ("wire_salt",
                                             &wire_salt),
@@ -7349,7 +7412,7 @@ postgres_lookup_transfer_by_deposit (
       GNUNET_PQ_result_spec_uint64 ("payment_target_uuid",
                                     &kyc->payment_target_uuid),
       GNUNET_PQ_result_spec_auto_from_type ("kyc_ok",
-                                            &ok8),
+                                            &kyc->ok),
       TALER_PQ_RESULT_SPEC_AMOUNT ("amount_with_fee",
                                    amount_with_fee),
       TALER_PQ_RESULT_SPEC_AMOUNT ("fee_deposit",
@@ -7377,7 +7440,6 @@ postgres_lookup_transfer_by_deposit (
         return GNUNET_DB_STATUS_SUCCESS_NO_RESULTS;
     }
     kyc->type = TALER_EXCHANGEDB_KYC_DEPOSIT;
-    kyc->ok = (0 != ok8);
     return qs;
   }
 }
@@ -8164,7 +8226,7 @@ deposit_serial_helper_cb (void *cls,
     struct TALER_EXCHANGEDB_Deposit deposit;
     struct GNUNET_TIME_Absolute exchange_timestamp;
     struct TALER_DenominationPublicKey denom_pub;
-    uint8_t done = 0;
+    bool done;
     uint64_t rowid;
     struct GNUNET_PQ_ResultSpec rs[] = {
       TALER_PQ_RESULT_SPEC_AMOUNT ("amount_with_fee",
@@ -8191,8 +8253,8 @@ deposit_serial_helper_cb (void *cls,
                                             &deposit.wire_salt),
       GNUNET_PQ_result_spec_string ("receiver_wire_account",
                                     &deposit.receiver_wire_account),
-      GNUNET_PQ_result_spec_auto_from_type ("done",
-                                            &done),
+      GNUNET_PQ_result_spec_bool ("done",
+                                  &done),
       GNUNET_PQ_result_spec_uint64 ("deposit_serial_id",
                                     &rowid),
       GNUNET_PQ_result_spec_end
@@ -8213,7 +8275,7 @@ deposit_serial_helper_cb (void *cls,
                    exchange_timestamp,
                    &deposit,
                    &denom_pub,
-                   (0 != done) ? true : false);
+                   done);
     GNUNET_PQ_cleanup_result (rs);
     if (GNUNET_OK != ret)
       break;
@@ -9783,8 +9845,8 @@ missing_wire_cb (void *cls,
     struct TALER_Amount amount;
     char *payto_uri;
     struct GNUNET_TIME_Absolute deadline;
-    uint8_t tiny;
-    uint8_t done;
+    bool tiny;
+    bool done;
     struct GNUNET_PQ_ResultSpec rs[] = {
       GNUNET_PQ_result_spec_uint64 ("deposit_serial_id",
                                     &rowid),
@@ -9796,10 +9858,10 @@ missing_wire_cb (void *cls,
                                     &payto_uri),
       TALER_PQ_result_spec_absolute_time ("wire_deadline",
                                           &deadline),
-      GNUNET_PQ_result_spec_auto_from_type ("tiny",
-                                            &tiny),
-      GNUNET_PQ_result_spec_auto_from_type ("done",
-                                            &done),
+      GNUNET_PQ_result_spec_bool ("tiny",
+                                  &tiny),
+      GNUNET_PQ_result_spec_bool ("done",
+                                  &done),
       GNUNET_PQ_result_spec_end
     };
 
@@ -9923,22 +9985,18 @@ postgres_lookup_auditor_status (
     GNUNET_PQ_query_param_auto_from_type (auditor_pub),
     GNUNET_PQ_query_param_end
   };
-  uint8_t enabled8 = 0;
   struct GNUNET_PQ_ResultSpec rs[] = {
     GNUNET_PQ_result_spec_string ("auditor_url",
                                   auditor_url),
-    GNUNET_PQ_result_spec_auto_from_type ("is_active",
-                                          &enabled8),
+    GNUNET_PQ_result_spec_bool ("is_active",
+                                enabled),
     GNUNET_PQ_result_spec_end
   };
-  enum GNUNET_DB_QueryStatus qs;
 
-  qs = GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
-                                                 "lookup_auditor_status",
-                                                 params,
-                                                 rs);
-  *enabled = (0 != enabled8);
-  return qs;
+  return GNUNET_PQ_eval_prepared_singleton_select (pg->conn,
+                                                   "lookup_auditor_status",
+                                                   params,
+                                                   rs);
 }
 
 
@@ -9996,12 +10054,11 @@ postgres_update_auditor (void *cls,
                          bool enabled)
 {
   struct PostgresClosure *pg = cls;
-  uint8_t enabled8 = enabled ? 1 : 0;
   struct GNUNET_PQ_QueryParam params[] = {
     GNUNET_PQ_query_param_auto_from_type (auditor_pub),
     GNUNET_PQ_query_param_string (auditor_url),
     GNUNET_PQ_query_param_string (auditor_name),
-    GNUNET_PQ_query_param_auto_from_type (&enabled8),
+    GNUNET_PQ_query_param_bool (enabled),
     GNUNET_PQ_query_param_absolute_time (&change_date),
     GNUNET_PQ_query_param_end
   };
@@ -10091,10 +10148,9 @@ postgres_update_wire (void *cls,
                       bool enabled)
 {
   struct PostgresClosure *pg = cls;
-  uint8_t enabled8 = enabled ? 1 : 0;
   struct GNUNET_PQ_QueryParam params[] = {
     GNUNET_PQ_query_param_string (payto_uri),
-    GNUNET_PQ_query_param_auto_from_type (&enabled8),
+    GNUNET_PQ_query_param_bool (enabled),
     GNUNET_PQ_query_param_absolute_time (&change_date),
     GNUNET_PQ_query_param_end
   };
@@ -11767,7 +11823,9 @@ libtaler_plugin_exchangedb_postgres_init (void *cls)
   plugin->get_latest_reserve_in_reference =
     &postgres_get_latest_reserve_in_reference;
   plugin->get_withdraw_info = &postgres_get_withdraw_info;
-  plugin->insert_withdraw_info = &postgres_insert_withdraw_info;
+  // plugin->insert_withdraw_info = &postgres_insert_withdraw_info;
+  plugin->do_withdraw = &postgres_do_withdraw;
+  plugin->do_withdraw_limit_check = &postgres_do_withdraw_limit_check;
   plugin->get_reserve_history = &postgres_get_reserve_history;
   plugin->select_withdraw_amounts_by_account
     = &postgres_select_withdraw_amounts_by_account;
diff --git a/src/exchangedb/test_exchangedb.c b/src/exchangedb/test_exchangedb.c
index 6807c242..12cff490 100644
--- a/src/exchangedb/test_exchangedb.c
+++ b/src/exchangedb/test_exchangedb.c
@@ -1659,10 +1659,26 @@ run (void *cls)
   cbc.reserve_pub = reserve_pub;
   cbc.amount_with_fee = value;
   GNUNET_assert (GNUNET_OK ==
-                 TALER_amount_set_zero (CURRENCY, &cbc.withdraw_fee));
-  FAILIF (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT !=
-          plugin->insert_withdraw_info (plugin->cls,
-                                        &cbc));
+                 TALER_amount_set_zero (CURRENCY,
+                                        &cbc.withdraw_fee));
+  {
+    bool found;
+    bool balance_ok;
+    struct TALER_EXCHANGEDB_KycStatus kyc;
+    uint64_t ruuid;
+
+    FAILIF (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT !=
+            plugin->do_withdraw (plugin->cls,
+                                 &cbc,
+                                 now,
+                                 &found,
+                                 &balance_ok,
+                                 &kyc,
+                                 &ruuid));
+    GNUNET_assert (found);
+    GNUNET_assert (balance_ok);
+    GNUNET_assert (! kyc.ok);
+  }
   FAILIF (GNUNET_OK !=
           check_reserve (&reserve_pub,
                          value.value,