diff --git a/db/comdb2.h b/db/comdb2.h
index 075da5a144..396b16d151 100644
--- a/db/comdb2.h
+++ b/db/comdb2.h
@@ -1419,8 +1419,9 @@ struct ireq {
 
     /* List of indices that we've written to detect uncommittable upsert txns */
     hash_t *vfy_idx_hash; 
-
     int dup_key_insert;
+    /* Whether this txn has ignored upsert conflicts */
+    int upsert_ignored;
 
     /* List of genids that we've written to detect uncommittable txn's */
     hash_t *vfy_genid_hash;
diff --git a/db/constraints.c b/db/constraints.c
index 1a628bedc4..421005fb8f 100644
--- a/db/constraints.c
+++ b/db/constraints.c
@@ -1162,10 +1162,10 @@ int upsert_collision_should_force_verify_error(int flags, int ixnum)
         - If the client did 'insert ... on conflict ...', then upsert_idx will
         specify the index passed in the on conflict clause
         - If the client did 'replace into ...', then upsert_idx will be
-        MAXINDEX + 1
+        MAXINDEX + 1 (UPSERT_CONFLICT_ALL_INDEXES)
     */
     const int upsert_idx = flags >> 8;
-    return upsert_idx == ixnum || upsert_idx == MAXINDEX + 1;
+    return upsert_idx == ixnum || upsert_idx == UPSERT_CONFLICT_ALL_INDEXES;
 }
 
 int delayed_key_adds(struct ireq *iq, void *trans, int *blkpos, int *ixout,
diff --git a/db/handle_buf.c b/db/handle_buf.c
index 6471406773..a568aaef0a 100644
--- a/db/handle_buf.c
+++ b/db/handle_buf.c
@@ -639,6 +639,7 @@ void *thd_req(void *vthd)
             }
             thd->iq->vfy_idx_track = 0;
             thd->iq->dup_key_insert = 0;
+            thd->iq->upsert_ignored = 0;
 #if 0
             fprintf(stderr, "%s:%d: THD=%p relablk iq=%p\n", __func__, __LINE__, pthread_self(), thd->iq);
 #endif
diff --git a/db/indices.c b/db/indices.c
index 6332f3dca9..6c127d5ea4 100644
--- a/db/indices.c
+++ b/db/indices.c
@@ -264,6 +264,21 @@ int track_record_index(struct ireq *iq, int ixnum, void *key, int ixkeylen)
     return is_dup;
 }
 
+static int check_upsert_index(struct ireq *iq, void *trans, int idx, blob_buffer_t *blobs, size_t maxblobs,
+                              int *opfailcode, int *ixfailnum, int *retrc, void *od_dta, size_t od_len,
+                              unsigned long long ins_keys)
+{
+    /* Ignore dup keys */
+    if (iq->usedb->ix_dupes[idx]) {
+        return 0;
+    }
+    /* Check for partial keys only when needed. */
+    if (gbl_partial_indexes && iq->usedb->ix_partial && !(ins_keys & (1ULL << idx))) {
+        return 0;
+    }
+    return check_index(iq, trans, idx, blobs, maxblobs, opfailcode, ixfailnum, retrc, od_dta, od_len, ins_keys);
+}
+
 /* If a specific index has been used in the ON CONFLICT (idx) DO NOTHING
  * clause (aka upsert target/index), then we must first perform check for
  * that particular index and bail out (ignore) if there's a similar entry
@@ -277,42 +292,21 @@ int check_for_upsert(struct ireq *iq, void *trans, blob_buffer_t *blobs, size_t
     int upsert_idx = rec_flags >> 8;
 
    /* Perform the check for upsert index first. */
-    if (upsert_idx != MAXINDEX + 1) {
-
-        /* It must be a unique key. */
-        assert(iq->usedb->ix_dupes[upsert_idx] == 0);
-
-        /* Check for partial keys only when needed. */
-        if (gbl_partial_indexes && iq->usedb->ix_partial &&
-            !(ins_keys & (1ULL << upsert_idx))) {
-            /* NOOP */
-        } else {
-            rc = check_index(iq, trans, upsert_idx, blobs, maxblobs, opfailcode, ixfailnum, retrc, od_dta, od_len,
-                             ins_keys);
-            if (rc) {
-                return rc;
-            }
+    if (upsert_idx != UPSERT_CONFLICT_ALL_INDEXES) {
+        rc = check_upsert_index(iq, trans, upsert_idx, blobs, maxblobs, opfailcode, ixfailnum, retrc, od_dta, od_len,
+                                ins_keys);
+        if (rc) {
+            return rc;
         }
     }
 
     for (int ixnum = 0; ixnum < iq->usedb->nix; ixnum++) {
         /* Skip check for upsert index, was already checked above. */
-        if ((upsert_idx != MAXINDEX + 1) && (ixnum == upsert_idx)) {
-            continue;
-        }
-
-        /* Ignore dup keys */
-        if (iq->usedb->ix_dupes[ixnum] != 0) {
+        if ((upsert_idx != UPSERT_CONFLICT_ALL_INDEXES) && (ixnum == upsert_idx)) {
             continue;
         }
-
-        /* Check for partial keys only when needed. */
-        if (gbl_partial_indexes && iq->usedb->ix_partial &&
-            !(ins_keys & (1ULL << ixnum))) {
-            continue;
-        }
-
-        rc = check_index(iq, trans, ixnum, blobs, maxblobs, opfailcode, ixfailnum, retrc, od_dta, od_len, ins_keys);
+        rc = check_upsert_index(iq, trans, ixnum, blobs, maxblobs, opfailcode, ixfailnum, retrc, od_dta, od_len,
+                                ins_keys);
         if (rc) {
             return rc;
         }
diff --git a/db/indices.h b/db/indices.h
index 08398b6a68..bb4ff3cb49 100644
--- a/db/indices.h
+++ b/db/indices.h
@@ -17,6 +17,9 @@
 #ifndef INCLUDED_INDICES_H
 #define INCLUDED_INDICES_H
 
+#include <cdb2_constants.h>
+#define UPSERT_CONFLICT_ALL_INDEXES (MAXINDEX + 1)
+
 int track_record_index(struct ireq *iq, int ixnum, void *key, int ixkeylen);
 
 int check_for_upsert(struct ireq *iq, void *trans, blob_buffer_t *blobs, size_t maxblobs, int *opfailcode,
diff --git a/db/osqlblockproc.c b/db/osqlblockproc.c
index 42b7d30383..ef36858c82 100644
--- a/db/osqlblockproc.c
+++ b/db/osqlblockproc.c
@@ -1183,6 +1183,8 @@ static int apply_changes(struct ireq *iq, blocksql_tran_t *tran, void *iq_tran,
         hash_clear(iq->vfy_idx_hash);
     }
 
+    iq->upsert_ignored = 0;
+
     /* create a cursor */
     dbc = bdb_temp_table_cursor(thedb->bdb_env, tran->db, NULL, &bdberr);
     if (!dbc || bdberr) {
diff --git a/db/osqlcomm.c b/db/osqlcomm.c
index ae40ac5955..8410d1cc7c 100644
--- a/db/osqlcomm.c
+++ b/db/osqlcomm.c
@@ -57,6 +57,7 @@
 #include "logical_cron.h"
 #include "sc_logic.h"
 #include "eventlog.h"
+#include "indices.h"
 #include <disttxn.h>
 
 #define MAX_CLUSTER REPMAX
@@ -7331,7 +7332,7 @@ int osql_process_packet(struct ireq *iq, uuid_t uuid, void *trans, char **pmsg,
                           get_keynm_from_db_idx(iq->usedb, err->ixnum),
                           iq->usedb->tablename, err->ixnum);
                     err->errcode = ERR_UNCOMMITTABLE_TXN;
-                    goto done_delete;
+                    goto done_insert;
                 }
 
                 if (upsert_collision_should_force_verify_error(dt.upsert_flags, err->ixnum)) {
@@ -7341,20 +7342,23 @@ int osql_process_packet(struct ireq *iq, uuid_t uuid, void *trans, char **pmsg,
 
                 if ((dt.upsert_flags & OSQL_IGNORE_FAILURE) != 0) {
                     const int upsert_idx = dt.upsert_flags >> 8;
-                    if (upsert_idx == MAXINDEX + 1) {
+                    if (upsert_idx == UPSERT_CONFLICT_ALL_INDEXES) {
                         /* We're asked to ignore DUPs for all unique indices, no insert took place.*/
+                        iq->upsert_ignored = 1;
                         err->errcode = 0;
                         rc = 0;
-                        goto done_delete;
+                        goto done_insert;
                     } else if ((dt.upsert_flags & OSQL_FORCE_VERIFY) == 1) {
+                        iq->upsert_ignored = 0;
                         err->errcode = 0;
                         rc = 0;
-                        goto done_delete;
+                        goto done_insert;
                     } else if (upsert_idx == err->ixnum) {
                         /* We're asked to ignore DUPs for this particular * index, no insert took place.*/
+                        iq->upsert_ignored = 1;
                         err->errcode = 0;
                         rc = 0;
-                        goto done_delete;
+                        goto done_insert;
                     }
                 }
 
@@ -7377,7 +7381,7 @@ int osql_process_packet(struct ireq *iq, uuid_t uuid, void *trans, char **pmsg,
                        rrn, bdb_genid_to_host_order(newgenid));
 
             if (0) {
-done_delete:
+            done_insert:
                 EVENTLOG_DEBUG(
                     uuidstr_t ustr;
                     comdb2uuidstr(uuid, ustr);
diff --git a/db/toblock.c b/db/toblock.c
index 14ef5bdf5b..9978fdac86 100644
--- a/db/toblock.c
+++ b/db/toblock.c
@@ -5079,6 +5079,10 @@ static int toblock_main_int(struct javasp_trans_state *javasp_trans_handle, stru
         } else {
             nops += tmpnops;
             iq->sorese->nops = nops;
+            if (tmpnops == 0 && iq->upsert_ignored) {
+                logmsg(LOGMSG_DEBUG, "upsert did not insert, skipping constraints\n");
+                goto serializable_check;
+            }
         }
     }
 
@@ -5230,6 +5234,7 @@ static int toblock_main_int(struct javasp_trans_state *javasp_trans_handle, stru
             GOTOBACKOUT;
     }
 
+serializable_check:
     Pthread_rwlock_rdlock(&commit_lock);
     hascommitlock = 1;
     if (iq->arr || iq->selectv_arr) {