diff --git a/ext/session/sessionnoop.test b/ext/session/sessionnoop.test
index 5549773440..16c60b7abf 100644
--- a/ext/session/sessionnoop.test
+++ b/ext/session/sessionnoop.test
@@ -1,4 +1,4 @@
-# 2011 March 07
+# 2021 Februar 20
 #
 # The author disclaims copyright to this source code.  In place of
 # a legal notice, here is a blessing:
@@ -20,159 +20,166 @@ ifcapable !session {finish_test; return}
 
 set testprefix sessionnoop
 
-foreach {tn wo} {
-  1 ""
-  2 " WITHOUT ROWID "
+#-------------------------------------------------------------------------
+# Test plan:
+#
+#   1.*: Test that concatenating changesets cannot produce a noop UPDATE.
+#   2.*: Test that rebasing changesets cannot produce a noop UPDATE.
+#   3.*: Test that sqlite3changeset_apply() ignores noop UPDATE changes.
+#
+
+do_execsql_test 1.0 {
+  CREATE TABLE t1(a PRIMARY KEY, b, c, d);
+  INSERT INTO t1 VALUES(1, 1, 1, 1);
+  INSERT INTO t1 VALUES(2, 2, 2, 2);
+  INSERT INTO t1 VALUES(3, 3, 3, 3);
+}
+
+proc do_concat_test {tn sql1 sql2 res} {
+  uplevel [list do_test $tn [subst -nocommands {
+    set C1 [changeset_from_sql {$sql1}]
+    set C2 [changeset_from_sql {$sql2}]
+    set C3 [sqlite3changeset_concat [set C1] [set C2]]
+    set got [list]
+    sqlite3session_foreach elem [set C3] { lappend got [set elem] }
+    set got
+  }] [list {*}$res]]
+}
+
+do_concat_test 1.1 {
+  UPDATE t1 SET c=c+1;
+} {
+  UPDATE t1 SET c=c-1;
 } {
-  reset_db
-  eval [string map [list %WO% $wo] {
-do_execsql_test $tn.1.0 {
-  CREATE TABLE t1(a PRIMARY KEY, b, c) %WO%;
-  INSERT INTO t1 VALUES('a', 'A', 'AAA');
-  INSERT INTO t1 VALUES('b', 'B', 'BBB');
-  INSERT INTO t1 VALUES('c', 'C', 'CCC');
-  INSERT INTO t1 VALUES('d', 'D', 'DDD');
-  INSERT INTO t1 VALUES('e', 'E', 'EEE');
 }
 
-forcedelete test.db2
-sqlite3 db2 test.db2
-
-do_execsql_test -db db2 $tn.1.1 {
-  CREATE TABLE t1(a PRIMARY KEY, b, c) %WO%;
-  INSERT INTO t1 VALUES('a', 'A', 'AAA');
-  INSERT INTO t1 VALUES('b', 'B', '123');
-  INSERT INTO t1 VALUES('c', 'C', 'CCC');
-  INSERT INTO t1 VALUES('e', 'E', 'EEE');
-  INSERT INTO t1 VALUES('f', 'F', 'FFF');
-}
-
-set C [changeset_from_sql {
-  UPDATE t1 SET c='123' WHERE a='b';
-  DELETE FROM t1 WHERE a='d';
-  INSERT INTO t1 VALUES('f', 'F', 'FFF');
-}]
-
-
-set ::conflict_list [list]
-proc xConflict {args} {
-  lappend ::conflict_list $args
-  return "OMIT"
-}
-do_test $tn.1.2 {
-  sqlite3changeset_apply_v2 db2 $C xConflict
-  set ::conflict_list
-} [list {*}{
-  {UPDATE t1 DATA {t b {} {} t BBB} {{} {} {} {} t 123} {t b t B t 123}}
-  {INSERT t1 CONFLICT {t f t F t FFF} {t f t F t FFF}}
-  {DELETE t1 NOTFOUND {t d t D t DDD}}
-}]
-do_test $tn.1.3 {
-  set ::conflict_list [list]
-  sqlite3changeset_apply_v2 db2 $C xConflict
-  set ::conflict_list
-} [list {*}{
-  {UPDATE t1 DATA {t b {} {} t BBB} {{} {} {} {} t 123} {t b t B t 123}}
-  {INSERT t1 CONFLICT {t f t F t FFF} {t f t F t FFF}}
-  {DELETE t1 NOTFOUND {t d t D t DDD}}
-}]
-
-do_test $tn.1.4 {
-  set ::conflict_list [list]
-  sqlite3changeset_apply_v2 -ignorenoop db2 $C xConflict
-  set ::conflict_list
-} {}
-
-do_execsql_test -db db2 1.5 {
-  UPDATE t1 SET b='G' WHERE a='f';
-  UPDATE t1 SET c='456' WHERE a='b';
-}
-
-do_test $tn.1.6 {
-  set ::conflict_list [list]
-  sqlite3changeset_apply_v2 -ignorenoop db2 $C xConflict
-  set ::conflict_list
-} [list {*}{
-  {UPDATE t1 DATA {t b {} {} t BBB} {{} {} {} {} t 123} {t b t B t 456}}
-  {INSERT t1 CONFLICT {t f t F t FFF} {t f t G t FFF}}
-}]
-
-db2 close
-
-#--------------------------------------------------------------------------
-
-reset_db
-forcedelete test.db2
-sqlite3 db2 test.db2
-do_execsql_test $tn.2.0 {
-  CREATE TABLE t1(a PRIMARY KEY, b) %WO%;
-}
-do_execsql_test -db db2 $tn.2.1 {
-  CREATE TABLE t1(a PRIMARY KEY, b, c DEFAULT 'val') %WO%;
-}
-
-do_test $tn.2.2 {
-  do_then_apply_sql -ignorenoop {
-    INSERT INTO t1 VALUES(1, 2);
-  }
-  do_then_apply_sql -ignorenoop {
-    UPDATE t1 SET b=2 WHERE a=1
-  }
-} {}
-
-
-}]
-}
-
-db2 close
-
 #-------------------------------------------------------------------------
 reset_db
-forcedelete test.db2
+do_execsql_test 2.0 {
+  CREATE TABLE t1(a PRIMARY KEY, b, c);
+  INSERT INTO t1 VALUES(1, 1, 1);
+  INSERT INTO t1 VALUES(2, 2, 2);
+  INSERT INTO t1 VALUES(3, 3, 3);
+}
+
+proc do_rebase_test {tn sql_local sql_remote conflict_res expected} {
+  proc xConflict {args} [list return $conflict_res]
+
+  uplevel [list \
+    do_test $tn [subst -nocommands {
+      execsql BEGIN
+        set c_remote [changeset_from_sql {$sql_remote}]
+      execsql ROLLBACK
+
+      execsql BEGIN
+        set c_local [changeset_from_sql {$sql_local}]
+        set base [sqlite3changeset_apply_v2 db [set c_remote] xConflict]
+      execsql ROLLBACK
+
+      sqlite3rebaser_create R
+      R config [set base]
+      set res [list]
+      sqlite3session_foreach elem [R rebase [set c_local]] { 
+        lappend res [set elem] 
+      }
+      R delete
+      set res
+    }] [list {*}$expected]
+  ]
+}
+
+do_rebase_test 2.1 {
+  UPDATE t1 SET c=2 WHERE a=1;              -- local
+} {
+  UPDATE t1 SET c=3 WHERE a=1;              -- remote
+} OMIT {
+  {UPDATE t1 0 X.. {i 1 {} {} i 3} {{} {} {} {} i 2}}
+}
+
+do_rebase_test 2.2 {
+  UPDATE t1 SET c=2 WHERE a=1;              -- local
+} {
+  UPDATE t1 SET c=3 WHERE a=1;              -- remote
+} REPLACE {
+}
+
+do_rebase_test 2.3.1 {
+  UPDATE t1 SET c=4 WHERE a=1;              -- local
+} {
+  UPDATE t1 SET c=4 WHERE a=1               -- remote
+} OMIT {
+  {UPDATE t1 0 X.. {i 1 {} {} i 4} {{} {} {} {} i 4}}
+}
+
+do_rebase_test 2.3.2 {
+  UPDATE t1 SET c=5 WHERE a=1;              -- local
+} {
+  UPDATE t1 SET c=5 WHERE a=1               -- remote
+} REPLACE {
+}
+
+#-------------------------------------------------------------------------
+#
+reset_db
 do_execsql_test 3.0 {
-  CREATE TABLE xyz(a, b, c, PRIMARY KEY(a, b), UNIQUE(c));
-  ANALYZE;
-  WITH s(i) AS (
-    VALUES(1) UNION ALL SELECT i+1 FROM s WHERE i<100
-  )
-  INSERT INTO xyz SELECT i, i, i FROM s;
-  VACUUM INTO 'test.db2';
+  CREATE TABLE t1(a INTEGER PRIMARY KEY, b, c);
+  INSERT INTO t1 VALUES(1, 1, 1);
+  INSERT INTO t1 VALUES(2, 2, 2);
+  INSERT INTO t1 VALUES(3, 3, 3);
+  INSERT INTO t1 VALUES(4, 4, 4);
 }
 
-set C [changeset_from_sql { ANALYZE }]
-sqlite3 db2 test.db2
+# Arg $pkstr contains one character for each column in the table. An
+# "X" for PK column, or a "." for a non-PK.
+#
+proc mk_tbl_header {name pkstr} {
+  set ret [binary format H2c 54 [string length $pkstr]]
+  foreach i [split $pkstr {}] {
+    if {$i=="X"} {
+      append ret [binary format H2 01]
+    } else {
+      if {$i!="."} {error "bad pkstr: $pkstr ($i)"}
+      append ret [binary format H2 00]
+    }
+  }
+  append ret $name
+  append ret [binary format H2 00]
+  set ret
+}
 
-set ::conflict_list [list]
-proc xConflict {args} { lappend ::conflict_list $args ; return "OMIT" }
+proc mk_update_change {args} {
+  set ret [binary format H2H2 17 00]
+  foreach a $args {
+    if {$a==""} {
+      append ret [binary format H2 00]
+    } else {
+      append ret [binary format H2W 01 $a]
+    }
+  }
+  set ret
+}
+
+proc xConflict {args} { return "ABORT" }
 do_test 3.1 {
-  sqlite3changeset_apply_v2 db2 $C xConflict
-  set ::conflict_list
+  set    C [mk_tbl_header t1 X..]
+  append C [mk_update_change    1 {} 1   {} {}  500]
+  append C [mk_update_change    2 {} {}  {} {}  {}]
+  append C [mk_update_change    3 3  {}  {} 600 {}]
+  append C [mk_update_change    4 {} {}  {} {}  {}]
+
+  sqlite3changeset_apply_v2 db $C xConflict
 } {}
-
-do_test 3.2 {
-  sqlite3changeset_apply_v2 -ignorenoop db2 $C xConflict
-  set ::conflict_list
-} {}
-
-do_test 3.3 {
-  sqlite3changeset_apply_v2 db2 $C xConflict
-  set ::conflict_list
-} [list {*}{
-  {INSERT sqlite_stat1 CONFLICT {t xyz t sqlite_autoindex_xyz_1 t {100 1 1}} {t xyz t sqlite_autoindex_xyz_1 t {100 1 1}}} 
-  {INSERT sqlite_stat1 CONFLICT {t xyz t sqlite_autoindex_xyz_2 t {100 1}} {t xyz t sqlite_autoindex_xyz_2 t {100 1}}}
-}]
-
-do_execsql_test -db db2 3.4 {
-  UPDATE sqlite_stat1 SET stat='200 1 1' WHERE idx='sqlite_autoindex_xyz_1';
+do_execsql_test 3.2 {
+  SELECT * FROM t1
+} {
+  1 1 500
+  2 2 2
+  3 600 3
+  4 4 4
 }
 
-do_test 3.5 {
-  set ::conflict_list [list]
-  sqlite3changeset_apply_v2 -ignorenoop db2 $C xConflict
-  set ::conflict_list
-} [list {*}{
-  {INSERT sqlite_stat1 CONFLICT {t xyz t sqlite_autoindex_xyz_1 t {100 1 1}} {t xyz t sqlite_autoindex_xyz_1 t {200 1 1}}} 
-}]
+
+
 
 
 
diff --git a/ext/session/sessionnoop2.test b/ext/session/sessionnoop2.test
new file mode 100644
index 0000000000..5549773440
--- /dev/null
+++ b/ext/session/sessionnoop2.test
@@ -0,0 +1,180 @@
+# 2011 March 07
+#
+# The author disclaims copyright to this source code.  In place of
+# a legal notice, here is a blessing:
+#
+#    May you do good and not evil.
+#    May you find forgiveness for yourself and forgive others.
+#    May you share freely, never taking more than you give.
+#
+#***********************************************************************
+# This file implements regression tests for SQLite library.
+#
+
+if {![info exists testdir]} {
+  set testdir [file join [file dirname [info script]] .. .. test]
+} 
+source [file join [file dirname [info script]] session_common.tcl]
+source $testdir/tester.tcl
+ifcapable !session {finish_test; return}
+
+set testprefix sessionnoop
+
+foreach {tn wo} {
+  1 ""
+  2 " WITHOUT ROWID "
+} {
+  reset_db
+  eval [string map [list %WO% $wo] {
+do_execsql_test $tn.1.0 {
+  CREATE TABLE t1(a PRIMARY KEY, b, c) %WO%;
+  INSERT INTO t1 VALUES('a', 'A', 'AAA');
+  INSERT INTO t1 VALUES('b', 'B', 'BBB');
+  INSERT INTO t1 VALUES('c', 'C', 'CCC');
+  INSERT INTO t1 VALUES('d', 'D', 'DDD');
+  INSERT INTO t1 VALUES('e', 'E', 'EEE');
+}
+
+forcedelete test.db2
+sqlite3 db2 test.db2
+
+do_execsql_test -db db2 $tn.1.1 {
+  CREATE TABLE t1(a PRIMARY KEY, b, c) %WO%;
+  INSERT INTO t1 VALUES('a', 'A', 'AAA');
+  INSERT INTO t1 VALUES('b', 'B', '123');
+  INSERT INTO t1 VALUES('c', 'C', 'CCC');
+  INSERT INTO t1 VALUES('e', 'E', 'EEE');
+  INSERT INTO t1 VALUES('f', 'F', 'FFF');
+}
+
+set C [changeset_from_sql {
+  UPDATE t1 SET c='123' WHERE a='b';
+  DELETE FROM t1 WHERE a='d';
+  INSERT INTO t1 VALUES('f', 'F', 'FFF');
+}]
+
+
+set ::conflict_list [list]
+proc xConflict {args} {
+  lappend ::conflict_list $args
+  return "OMIT"
+}
+do_test $tn.1.2 {
+  sqlite3changeset_apply_v2 db2 $C xConflict
+  set ::conflict_list
+} [list {*}{
+  {UPDATE t1 DATA {t b {} {} t BBB} {{} {} {} {} t 123} {t b t B t 123}}
+  {INSERT t1 CONFLICT {t f t F t FFF} {t f t F t FFF}}
+  {DELETE t1 NOTFOUND {t d t D t DDD}}
+}]
+do_test $tn.1.3 {
+  set ::conflict_list [list]
+  sqlite3changeset_apply_v2 db2 $C xConflict
+  set ::conflict_list
+} [list {*}{
+  {UPDATE t1 DATA {t b {} {} t BBB} {{} {} {} {} t 123} {t b t B t 123}}
+  {INSERT t1 CONFLICT {t f t F t FFF} {t f t F t FFF}}
+  {DELETE t1 NOTFOUND {t d t D t DDD}}
+}]
+
+do_test $tn.1.4 {
+  set ::conflict_list [list]
+  sqlite3changeset_apply_v2 -ignorenoop db2 $C xConflict
+  set ::conflict_list
+} {}
+
+do_execsql_test -db db2 1.5 {
+  UPDATE t1 SET b='G' WHERE a='f';
+  UPDATE t1 SET c='456' WHERE a='b';
+}
+
+do_test $tn.1.6 {
+  set ::conflict_list [list]
+  sqlite3changeset_apply_v2 -ignorenoop db2 $C xConflict
+  set ::conflict_list
+} [list {*}{
+  {UPDATE t1 DATA {t b {} {} t BBB} {{} {} {} {} t 123} {t b t B t 456}}
+  {INSERT t1 CONFLICT {t f t F t FFF} {t f t G t FFF}}
+}]
+
+db2 close
+
+#--------------------------------------------------------------------------
+
+reset_db
+forcedelete test.db2
+sqlite3 db2 test.db2
+do_execsql_test $tn.2.0 {
+  CREATE TABLE t1(a PRIMARY KEY, b) %WO%;
+}
+do_execsql_test -db db2 $tn.2.1 {
+  CREATE TABLE t1(a PRIMARY KEY, b, c DEFAULT 'val') %WO%;
+}
+
+do_test $tn.2.2 {
+  do_then_apply_sql -ignorenoop {
+    INSERT INTO t1 VALUES(1, 2);
+  }
+  do_then_apply_sql -ignorenoop {
+    UPDATE t1 SET b=2 WHERE a=1
+  }
+} {}
+
+
+}]
+}
+
+db2 close
+
+#-------------------------------------------------------------------------
+reset_db
+forcedelete test.db2
+do_execsql_test 3.0 {
+  CREATE TABLE xyz(a, b, c, PRIMARY KEY(a, b), UNIQUE(c));
+  ANALYZE;
+  WITH s(i) AS (
+    VALUES(1) UNION ALL SELECT i+1 FROM s WHERE i<100
+  )
+  INSERT INTO xyz SELECT i, i, i FROM s;
+  VACUUM INTO 'test.db2';
+}
+
+set C [changeset_from_sql { ANALYZE }]
+sqlite3 db2 test.db2
+
+set ::conflict_list [list]
+proc xConflict {args} { lappend ::conflict_list $args ; return "OMIT" }
+do_test 3.1 {
+  sqlite3changeset_apply_v2 db2 $C xConflict
+  set ::conflict_list
+} {}
+
+do_test 3.2 {
+  sqlite3changeset_apply_v2 -ignorenoop db2 $C xConflict
+  set ::conflict_list
+} {}
+
+do_test 3.3 {
+  sqlite3changeset_apply_v2 db2 $C xConflict
+  set ::conflict_list
+} [list {*}{
+  {INSERT sqlite_stat1 CONFLICT {t xyz t sqlite_autoindex_xyz_1 t {100 1 1}} {t xyz t sqlite_autoindex_xyz_1 t {100 1 1}}} 
+  {INSERT sqlite_stat1 CONFLICT {t xyz t sqlite_autoindex_xyz_2 t {100 1}} {t xyz t sqlite_autoindex_xyz_2 t {100 1}}}
+}]
+
+do_execsql_test -db db2 3.4 {
+  UPDATE sqlite_stat1 SET stat='200 1 1' WHERE idx='sqlite_autoindex_xyz_1';
+}
+
+do_test 3.5 {
+  set ::conflict_list [list]
+  sqlite3changeset_apply_v2 -ignorenoop db2 $C xConflict
+  set ::conflict_list
+} [list {*}{
+  {INSERT sqlite_stat1 CONFLICT {t xyz t sqlite_autoindex_xyz_1 t {100 1 1}} {t xyz t sqlite_autoindex_xyz_1 t {200 1 1}}} 
+}]
+
+
+
+finish_test
+
diff --git a/manifest b/manifest
index 7eedebd097..395629ab8d 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\scountofview.test\sso\sthat\sit\sworks\swith\sSQLITE_OMIT_PROGRESS_CALLBACK\sbuilds.
-D 2023-03-09T15:08:06.155
+C Reinstate\ssome\stest\scases\saccidentally\sremoved\sby\s[cb023fe28560ce0f].
+D 2023-03-09T16:11:43.576
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -456,7 +456,8 @@ F ext/session/sessionfault.test 573bf027fb870d57bd4e7cf50822a3e4b17b2b9234074387
 F ext/session/sessionfault2.test b0d6a7c1d7398a7e800d84657404909c7d385965ea8576dc79ed344c46fbf41c
 F ext/session/sessioninvert.test 04075517a9497a80d39c495ba6b44f3982c7371129b89e2c52219819bc105a25
 F ext/session/sessionmem.test f2a735db84a3e9e19f571033b725b0b2daf847f3f28b1da55a0c1a4e74f1de09
-F ext/session/sessionnoop.test 5c9a882219e54711c98dccd2fd81392f189a59325e4fb5d8ed25e33a0c2f0ba2
+F ext/session/sessionnoop.test a9366a36a95ef85f8a3687856ebef46983df399541174cb1ede2ee53b8011bc7
+F ext/session/sessionnoop2.test 5c9a882219e54711c98dccd2fd81392f189a59325e4fb5d8ed25e33a0c2f0ba2
 F ext/session/sessionrebase.test ccfa716b23bd1d3b03217ee58cfd90c78d4b99f53e6a9a2f05e82363b9142810
 F ext/session/sessionsize.test 6f644aff31c7f1e4871e9ff3542766e18da68fc7e587b83a347ea9820a002dd8
 F ext/session/sessionstat1.test b039e38e2ba83767b464baf39b297cc0b1cc6f3292255cb467ea7e12d0d0280c
@@ -2049,8 +2050,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P a5db97fa17d15711ab19af70595912d342ffa326a9b7029d4deb2194ae72a9f0
-R 3676734d6a6a7d185c9f818259772398
+P 2fc7c3fcee05c2a251ceb3666f3f6e9014cfe6e2f8570b72c43f251067e6b252
+R 9fdb5fa7fb7a117f6c9f957b7fddcae2
 U dan
-Z dc232d0f3fec0eb69d0d02fdfd511211
+Z 5974dbe29f84c67ef0a243c359b4746e
 # Remove this line to create a well-formed Fossil manifest.
diff --git a/manifest.uuid b/manifest.uuid
index 30323296f9..118682aaf8 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-2fc7c3fcee05c2a251ceb3666f3f6e9014cfe6e2f8570b72c43f251067e6b252
\ No newline at end of file
+870de61f8ef8781f2f9969b012f5c1cb95b6bce1a9a4dcaf02945b7846c3aa83
\ No newline at end of file