diff --git a/src/include/taler_mintdb_plugin.h b/src/include/taler_mintdb_plugin.h
index f6fa27dbb..acdb0d2f5 100644
--- a/src/include/taler_mintdb_plugin.h
+++ b/src/include/taler_mintdb_plugin.h
@@ -985,7 +985,7 @@ struct TALER_MINTDB_Plugin
    * @param cls the @e cls of this struct with the plugin-specific state
    * @param sesssion database connection to use
    * @param session_hash hash to identify refresh session
-   * @param i set index (1st dimension), relating to #TALER_CNC_KAPPA
+   * @param cnc_index cut and choose index (1st dimension), relating to #TALER_CNC_KAPPA
    * @param num_newcoins coin index size of the @a commit_coins array
    * @param commit_coin array of coin commitments to store
    * @return #GNUNET_OK on success
@@ -995,7 +995,7 @@ struct TALER_MINTDB_Plugin
   (*insert_refresh_commit_coins) (void *cls,
                                   struct TALER_MINTDB_Session *sesssion,
                                   const struct GNUNET_HashCode *session_hash,
-                                  unsigned int i,
+                                  unsigned int cnc_index,
                                   unsigned int num_newcoins,
                                   const struct TALER_MINTDB_RefreshCommitCoin *commit_coins);
 
@@ -1007,7 +1007,7 @@ struct TALER_MINTDB_Plugin
    * @param cls the @e cls of this struct with the plugin-specific state
    * @param sesssion database connection to use
    * @param session_hash hash to identify refresh session
-   * @param i set index (1st dimension)
+   * @param cnc_index cut and choose set index (1st dimension)
    * @param num_coins size of the @a commit_coins array
    * @param[out] commit_coin array of coin commitments to return
    * @return #GNUNET_OK on success
@@ -1018,7 +1018,7 @@ struct TALER_MINTDB_Plugin
   (*get_refresh_commit_coins) (void *cls,
                                struct TALER_MINTDB_Session *sesssion,
                                const struct GNUNET_HashCode *session_hash,
-                               unsigned int i,
+                               unsigned int cnc_index,
                                unsigned int num_coins,
                                struct TALER_MINTDB_RefreshCommitCoin *commit_coins);
 
@@ -1030,7 +1030,7 @@ struct TALER_MINTDB_Plugin
    * @param cls the @e cls of this struct with the plugin-specific state
    * @param sesssion database connection to use
    * @param session_hash hash to identify refresh session
-   * @param i set index (1st dimension), relating to #TALER_CNC_KAPPA
+   * @param cnc_index cut and choose index (1st dimension), relating to #TALER_CNC_KAPPA
    * @param num_links size of the @a commit_link array
    * @param commit_links array of link information to store
    * @return #GNUNET_SYSERR on internal error, #GNUNET_OK on success
@@ -1039,7 +1039,7 @@ struct TALER_MINTDB_Plugin
   (*insert_refresh_commit_links) (void *cls,
                                   struct TALER_MINTDB_Session *sesssion,
                                   const struct GNUNET_HashCode *session_hash,
-                                  unsigned int i,
+                                  unsigned int cnc_index,
                                   unsigned int num_links,
                                   const struct TALER_MINTDB_RefreshCommitLinkP *commit_links);
 
@@ -1050,7 +1050,7 @@ struct TALER_MINTDB_Plugin
    * @param cls the @e cls of this struct with the plugin-specific state
    * @param sesssion database connection to use
    * @param session_hash hash to identify refresh session
-   * @param i set index (1st dimension)
+   * @param cnc_index cut and choose index (1st dimension)
    * @param num_links size of the @a links array to return
    * @param[out] links array link information to return
    * @return #GNUNET_SYSERR on internal error,
@@ -1061,7 +1061,7 @@ struct TALER_MINTDB_Plugin
   (*get_refresh_commit_links) (void *cls,
                                struct TALER_MINTDB_Session *sesssion,
                                const struct GNUNET_HashCode *session_hash,
-                               unsigned int i,
+                               unsigned int cnc_index,
                                unsigned int num_links,
                                struct TALER_MINTDB_RefreshCommitLinkP *links);
 
diff --git a/src/mintdb/plugin_mintdb_postgres.c b/src/mintdb/plugin_mintdb_postgres.c
index 31dc91a4f..6472e1fbe 100644
--- a/src/mintdb/plugin_mintdb_postgres.c
+++ b/src/mintdb/plugin_mintdb_postgres.c
@@ -2152,7 +2152,7 @@ postgres_get_refresh_order (void *cls,
  * @param cls the `struct PostgresClosure` with the plugin-specific state
  * @param session database connection to use
  * @param session_hash hash to identify refresh session
- * @param i set index (1st dimension)
+ * @param cnc_index cut and choose index (1st dimension)
  * @param num_newcoins coin index size of the @a commit_coins array
  * @param commit_coins array of coin commitments to store
  * @return #GNUNET_OK on success
@@ -2162,12 +2162,12 @@ static int
 postgres_insert_refresh_commit_coins (void *cls,
                                       struct TALER_MINTDB_Session *session,
                                       const struct GNUNET_HashCode *session_hash,
-                                      unsigned int i,
+                                      unsigned int cnc_index,
                                       unsigned int num_newcoins,
                                       const struct TALER_MINTDB_RefreshCommitCoin *commit_coins)
 {
   // FIXME: check logic! -- was written for single commit_coin! // #3831
-  uint16_t cnc_index_nbo = htons (i); // #3827
+  uint16_t cnc_index_nbo = htons (cnc_index); // #3827
   uint16_t newcoin_index_nbo = htons (num_newcoins); // #3827
   char *rle;
   size_t rle_size;
@@ -2306,29 +2306,28 @@ postgres_get_refresh_commit_coins (void *cls,
  * @param cls the `struct PostgresClosure` with the plugin-specific state
  * @param session database connection to use
  * @param session_hash hash to identify refresh session
- * FIXME: i/j -- better names, please!
- * @param i set index (1st dimension)
- * @param j coin index (2nd dimension), corresponds to melted (old) coins
- * @param commit_link link information to store
+ * @param cnc_index cut and choose index (1st dimension)
+ * @param num_links size of the @a links array to return
+ * @param[out] links array of link information to store return
  * @return #GNUNET_SYSERR on internal error, #GNUNET_OK on success
  */
 static int
 postgres_insert_refresh_commit_links (void *cls,
                                       struct TALER_MINTDB_Session *session,
                                       const struct GNUNET_HashCode *session_hash,
-                                      unsigned int i,
-                                      unsigned int j,
-                                      const struct TALER_MINTDB_RefreshCommitLinkP *commit_link)
+                                      unsigned int cnc_index,
+                                      unsigned int num_links,
+                                      const struct TALER_MINTDB_RefreshCommitLinkP *links)
 {
   // FIXME: check logic!
-  uint16_t cnc_index_nbo = htons (i); // #3827
-  uint16_t oldcoin_index_nbo = htons (j); // #3827
+  uint16_t cnc_index_nbo = htons (cnc_index); // #3827
+  uint16_t oldcoin_index_nbo = htons (num_links); // #3827
   struct TALER_PQ_QueryParam params[] = {
-    TALER_PQ_query_param_auto_from_type(session_hash),
-    TALER_PQ_query_param_auto_from_type(&commit_link->transfer_pub),
-    TALER_PQ_query_param_auto_from_type(&cnc_index_nbo),
-    TALER_PQ_query_param_auto_from_type(&oldcoin_index_nbo),
-    TALER_PQ_query_param_auto_from_type(&commit_link->shared_secret_enc),
+    TALER_PQ_query_param_auto_from_type (session_hash),
+    TALER_PQ_query_param_auto_from_type (&links->transfer_pub),
+    TALER_PQ_query_param_auto_from_type (&cnc_index_nbo),
+    TALER_PQ_query_param_auto_from_type (&oldcoin_index_nbo),
+    TALER_PQ_query_param_auto_from_type (&links->shared_secret_enc),
     TALER_PQ_query_param_end
   };
 
@@ -2360,7 +2359,7 @@ postgres_insert_refresh_commit_links (void *cls,
  * @param cls the `struct PostgresClosure` with the plugin-specific state
  * @param session database connection to use
  * @param session_hash hash to identify refresh session
- * @param i set index (1st dimension)
+ * @param cnc_index cut and choose index (1st dimension)
  * @param num_links size of the @a commit_link array
  * @param[out] links array of link information to return
  * @return #GNUNET_SYSERR on internal error,
@@ -2371,12 +2370,12 @@ static int
 postgres_get_refresh_commit_links (void *cls,
                                    struct TALER_MINTDB_Session *session,
                                    const struct GNUNET_HashCode *session_hash,
-                                   unsigned int i,
+                                   unsigned int cnc_index,
                                    unsigned int num_links,
                                    struct TALER_MINTDB_RefreshCommitLinkP *links)
 {
   // FIXME: check logic: was written for a single link!
-  uint16_t cnc_index_nbo = htons (i); // #3827
+  uint16_t cnc_index_nbo = htons (cnc_index); // #3827
   uint16_t oldcoin_index_nbo = htons (num_links); // #3827
 
   struct TALER_PQ_QueryParam params[] = {