diff --git a/manifest b/manifest
index d04f8b0c46..e36c760a79 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Add\sa\snew\sbuilt-in\ssubtype()\sfunction.
-D 2022-01-09T16:54:02.203
+C Merge\strunk\senhancements\sinto\sthe\sjson-in-core\sbranch.
+D 2022-01-09T19:36:39.850
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -494,7 +494,7 @@ F src/btmutex.c 8acc2f464ee76324bf13310df5692a262b801808984c1b79defb2503bbafadb6
 F src/btree.c 0e9f84f974e970fb373c15caa1624a281b3c33098cb9dd9021d6801c04eb4fde
 F src/btree.h 74d64b8f28cfa4a894d14d4ed64fa432cd697b98b61708d4351482ae15913e22
 F src/btreeInt.h ee9348c4cb9077243b049edc93a82c1f32ca48baeabf2140d41362b9f9139ff7
-F src/build.c 6e16f7b539bfc55149a039bf0cda26b089640339df6147070b072df2d1c4f771
+F src/build.c c72407a27a28982a384cd453a3a6b6992a1ceae8bd8d95e96d7fb9c0d645a32f
 F src/callback.c 4c19af69835787bfe790ac560f3071a824eb629f34e41f97b52ce5235c77de1c
 F src/complete.c a3634ab1e687055cd002e11b8f43eb75c17da23e
 F src/ctime.c b09ce320b78718d5e0c4a7a59b8705abe8ee4683d9fa4b33768fe347e1b2a42a
@@ -505,7 +505,7 @@ F src/delete.c 19814f621cde10b1771a0dea7fe25d3d7d39975b8d4be4888537d30860e7c08c
 F src/expr.c 827179c78d2ca7cc318392811de8151c60eacf7ce804b13e61bb7ef38f954846
 F src/fault.c 460f3e55994363812d9d60844b2a6de88826e007
 F src/fkey.c 5b73f7a7c00f06017531a5bd258cbc2c7a294e55a7f84a729fe27aa525242560
-F src/func.c 76a9ac772f67be5af9476e02ae0866f4919d1981f97ff16dedfe37a1c62cbf8e
+F src/func.c 8fddc42bce95d17938252a543f86fe29e479366e80fbd112a1822913b6247776
 F src/global.c 1f56aead86e8a18c4415638f5e6c4d0a0550427f4b3f5d065ba5164cc09c22e8
 F src/hash.c 8d7dda241d0ebdafb6ffdeda3149a412d7df75102cecfc1021c98d6219823b19
 F src/hash.h 3340ab6e1d13e725571d7cee6d3e3135f0779a7d8e76a9ce0a85971fa3953c51
@@ -538,7 +538,7 @@ F src/os_setup.h 0dbaea40a7d36bf311613d31342e0b99e2536586
 F src/os_unix.c f5ad51cfd024116db8531feab9efd831c2621436dca1464e4ff1e8af9bf3252e
 F src/os_win.c 77d39873836f1831a9b0b91894fec45ab0e9ca8e067dc8c549e1d1eca1566fe9
 F src/os_win.h 7b073010f1451abe501be30d12f6bc599824944a
-F src/pager.c 55a9a8c745c47a49e6541b1d634f6152e3f72f76c6dbb04fe24413986a928091
+F src/pager.c 5130bd602719ad9de1436def895da73973ee74382db02036be21238d0aa2ccfd
 F src/pager.h 4bf9b3213a4b2bebbced5eaa8b219cf25d4a82f385d093cd64b7e93e5285f66f
 F src/parse.y 04f61db1cdd7036c6d74baad1c342d3e3110cb0765c48fcfd3bdf4e974a1e5bb
 F src/pcache.c 084e638432c610f95aea72b8509f0845d2791293f39d1b82f0c0a7e089c3bb6b
@@ -1680,7 +1680,7 @@ F test/upfrom2.test 88d39cb755db5789541e645d4e2764abc697a56958f28a3f8451a0e9342b
 F test/upfrom3.test 6130f24ebf97f5ea865e5d2a14a2d543fe5428a62e87cc60f62d875e45c1f5f0
 F test/upfromfault.test 3a10075a0043f0c4fad6614b2c371f88a8ba5a4acab68b907438413865d6a8d6
 F test/upsert1.test b0ae2f58680c5205b4bc1cdeed3c3d444057c506f6c44494fa3eac60731d68a2
-F test/upsert2.test 9c3cdbb1a890227f6504ce4b0e3de68f4cdfa16bb21d8641208a9239896c5a09
+F test/upsert2.test 720e94d09f7362a282bc69b3c6b83d51daeaaf0440eb4920a08b86518b8c7496
 F test/upsert3.test 88d7d590a1948a9cb6eac1b54b0642f67a9f35a1fc0f19b200e97d5d39e3179c
 F test/upsert4.test 25d2a1da92f149331ae0c51ca6e3eee78189577585eab92de149900d62994fa5
 F test/upsert5.test fff0dcfce73c649204543088d8e5bde01172676063ec9b8f8fc7f195abc386fe
@@ -1938,8 +1938,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P e116501c2f0e594eb7a3dd804daa943cc508f32ded3078aed21b695ec83bcd4c
-R 28e65f1e2d788c0c1b31d4dbdc4f0a91
+P a25f4ce255c034fc694c33728aedb98289ebccda9c48920829ef780b92b8faee 71272caff5874137ad0b1ddfc22ced4bb66e6c97f7868fdae0347a186f589b38
+R 49fcbfca4503349519b1d6e2c92f7acf
 U drh
-Z fde45050a7eb088af98952ef4d939a27
+Z 4bb2ffcd67d474872b040ea5d2948b38
 # Remove this line to create a well-formed Fossil manifest.
diff --git a/manifest.uuid b/manifest.uuid
index 7d48848f7b..f20238fd7c 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-a25f4ce255c034fc694c33728aedb98289ebccda9c48920829ef780b92b8faee
\ No newline at end of file
+ea755771699dcbffe0ddfd204d42fae9b6e79e107485c725b8eb6caab92aacb8
\ No newline at end of file
diff --git a/src/build.c b/src/build.c
index b93dd91e1c..ce1c720800 100644
--- a/src/build.c
+++ b/src/build.c
@@ -170,7 +170,7 @@ void sqlite3FinishCoding(Parse *pParse){
       int i;
       int reg;
 
-      if( pReturning->nRetCol==0 ){
+      if( NEVER(pReturning->nRetCol==0) ){
         assert( CORRUPT_DB );
       }else{
         sqlite3VdbeAddOp0(v, OP_FkCheck);
@@ -266,7 +266,7 @@ void sqlite3FinishCoding(Parse *pParse){
 
       if( pParse->bReturning ){
         Returning *pRet = pParse->u1.pReturning;
-        if( pRet->nRetCol==0 ){
+        if( NEVER(pRet->nRetCol==0) ){
           assert( CORRUPT_DB );
         }else{
           sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pRet->iRetCur, pRet->nRetCol);
diff --git a/src/func.c b/src/func.c
index 596a1bb3ab..81accc9cc3 100644
--- a/src/func.c
+++ b/src/func.c
@@ -269,7 +269,7 @@ endInstrOOM:
 }
 
 /*
-** Implementation of the printf() function.
+** Implementation of the printf() (a.k.a. format()) SQL function.
 */
 static void printfFunc(
   sqlite3_context *context,
@@ -2261,6 +2261,7 @@ void sqlite3RegisterBuiltinFunctions(void){
     FUNCTION2(length,            1, 0, 0, lengthFunc,  SQLITE_FUNC_LENGTH),
     FUNCTION(instr,              2, 0, 0, instrFunc        ),
     FUNCTION(printf,            -1, 0, 0, printfFunc       ),
+    FUNCTION(format,            -1, 0, 0, printfFunc       ),
     FUNCTION(unicode,            1, 0, 0, unicodeFunc      ),
     FUNCTION(char,              -1, 0, 0, charFunc         ),
     FUNCTION(abs,                1, 0, 0, absFunc          ),
diff --git a/src/pager.c b/src/pager.c
index 24a2ce2c4c..26b8289605 100644
--- a/src/pager.c
+++ b/src/pager.c
@@ -5667,6 +5667,7 @@ int sqlite3PagerGet(
   DbPage **ppPage,    /* Write a pointer to the page here */
   int flags           /* PAGER_GET_XXX flags */
 ){
+  /* printf("PAGE %u\n", pgno); fflush(stdout); */
   return pPager->xGet(pPager, pgno, ppPage, flags);
 }
 
diff --git a/test/upsert2.test b/test/upsert2.test
index 1aa499e606..5cbc4656a4 100644
--- a/test/upsert2.test
+++ b/test/upsert2.test
@@ -72,7 +72,7 @@ do_execsql_test upsert2-300 {
   CREATE TABLE record(x TEXT, y TEXT);
   CREATE TRIGGER r1 BEFORE INSERT ON t1 BEGIN
     INSERT INTO record(x,y)
-        VALUES('before-insert',printf('%d,%d,%d',new.a,new.b,new.c));
+        VALUES('before-insert',format('%d,%d,%d',new.a,new.b,new.c));
   END;
   CREATE TRIGGER r2 AFTER INSERT ON t1 BEGIN
     INSERT INTO record(x,y)
@@ -80,7 +80,7 @@ do_execsql_test upsert2-300 {
   END;
   CREATE TRIGGER r3 BEFORE UPDATE ON t1 BEGIN
     INSERT INTO record(x,y)
-        VALUES('before-update',printf('%d,%d,%d/%d,%d,%d',
+        VALUES('before-update',format('%d,%d,%d/%d,%d,%d',
                                       old.a,old.b,old.c,new.a,new.b,new.c));
   END;
   CREATE TRIGGER r4 AFTER UPDATE ON t1 BEGIN
@@ -123,7 +123,7 @@ do_execsql_test upsert2-400 {
   CREATE TABLE t1(a INT PRIMARY KEY, b int, c DEFAULT 0) WITHOUT ROWID;
   CREATE TRIGGER r1 BEFORE INSERT ON t1 BEGIN
     INSERT INTO record(x,y)
-        VALUES('before-insert',printf('%d,%d,%d',new.a,new.b,new.c));
+        VALUES('before-insert',format('%d,%d,%d',new.a,new.b,new.c));
   END;
   CREATE TRIGGER r2 AFTER INSERT ON t1 BEGIN
     INSERT INTO record(x,y)
@@ -131,7 +131,7 @@ do_execsql_test upsert2-400 {
   END;
   CREATE TRIGGER r3 BEFORE UPDATE ON t1 BEGIN
     INSERT INTO record(x,y)
-        VALUES('before-update',printf('%d,%d,%d/%d,%d,%d',
+        VALUES('before-update',format('%d,%d,%d/%d,%d,%d',
                                       old.a,old.b,old.c,new.a,new.b,new.c));
   END;
   CREATE TRIGGER r4 AFTER UPDATE ON t1 BEGIN