diff --git a/Makefile.in b/Makefile.in
index 009ab2e061..3c9e7b3a96 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -582,6 +582,7 @@ SHELL_OPT += -DSQLITE_ENABLE_UNKNOWN_SQL_FUNCTION
 SHELL_OPT += -DSQLITE_ENABLE_STMTVTAB
 SHELL_OPT += -DSQLITE_ENABLE_DBPAGE_VTAB
 SHELL_OPT += -DSQLITE_ENABLE_DBSTAT_VTAB
+SHELL_OPT += -DSQLITE_ENABLE_OFFSET_SQL_FUNC
 FUZZERSHELL_OPT = -DSQLITE_ENABLE_JSON1
 FUZZCHECK_OPT = -DSQLITE_ENABLE_JSON1 -DSQLITE_ENABLE_MEMSYS5 -DSQLITE_OSS_FUZZ
 FUZZCHECK_OPT += -DSQLITE_MAX_MEMORY=50000000
diff --git a/Makefile.msc b/Makefile.msc
index 652bd81fd0..27eb23a240 100644
--- a/Makefile.msc
+++ b/Makefile.msc
@@ -1513,6 +1513,7 @@ FUZZDATA = \
 !IF $(DYNAMIC_SHELL)==0 && $(FOR_WIN10)==0
 SHELL_COMPILE_OPTS = $(SHELL_COMPILE_OPTS) -DSQLITE_ENABLE_JSON1 -DSQLITE_ENABLE_FTS4 -DSQLITE_ENABLE_EXPLAIN_COMMENTS -DSQLITE_ENABLE_STMTVTAB
 SHELL_COMPILE_OPTS = $(SHELL_COMPILE_OPTS) -DSQLITE_ENABLE_DBPAGE_VTAB -DSQLITE_ENABLE_DBSTAT_VTAB
+SHELL_COMPILE_OPTS = $(SHELL_COMPILE_OPTS) -DSQLITE_ENABLE_OFFSET_SQL_FUNC
 !ENDIF
 
 # <<mark>>
diff --git a/main.mk b/main.mk
index 8692450441..b46ffa1a52 100644
--- a/main.mk
+++ b/main.mk
@@ -509,6 +509,7 @@ SHELL_OPT += -DSQLITE_ENABLE_UNKNOWN_SQL_FUNCTION
 SHELL_OPT += -DSQLITE_ENABLE_STMTVTAB
 SHELL_OPT += -DSQLITE_ENABLE_DBPAGE_VTAB
 SHELL_OPT += -DSQLITE_ENABLE_DBSTAT_VTAB
+SHELL_OPT += -DSQLITE_ENABLE_OFFSET_SQL_FUNC
 FUZZERSHELL_OPT = -DSQLITE_ENABLE_JSON1
 FUZZCHECK_OPT = -DSQLITE_ENABLE_JSON1 -DSQLITE_ENABLE_MEMSYS5
 FUZZCHECK_OPT += -DSQLITE_MAX_MEMORY=50000000
diff --git a/manifest b/manifest
index 3e7d60e06a..682ec0eee7 100644
--- a/manifest
+++ b/manifest
@@ -1,8 +1,8 @@
-C Add\stest\scases\sfor\sthe\sundocumented\sbehavior\sof\sduplicate\scolumns\son\san\nINSERT\sor\sUPDATE.
-D 2017-12-29T12:50:43.938
-F Makefile.in ceb40bfcb30ebba8e1202b34c56ff7e13e112f9809e2381d99be32c2726058f5
+C Add\ssupport\sfor\sthe\ssqlite_unsupported_offset()\sSQL\sfunction\sif\sand\sonly\nif\scompiled\susing\s-DSQLITE_ENABLE_OFFSET_SQL_FUNC.\s\sUse\sthat\sdefinition\nwhen\scompiling\sthe\scommand-line\sshell.
+D 2017-12-29T17:21:21.319
+F Makefile.in 804c347948b0ad5a962aea3e59413e897227e0173d0e76910f11f473e6c7ae9b
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
-F Makefile.msc 6480671f7c129e61208d69492b3c71ce4310d49fceac83cfb17f1c081e242b69
+F Makefile.msc 57dcce0595d4a0c4b94b6f6ba732b8e33540358adf5fb8e1aa8389d34a9677e8
 F README.md eeae1e552f93ef72ef7c5b8f6647b368a001c28820ad1df179d3dae602bef681
 F VERSION 0c10cdfed866fdd2d80434f64f042c3330f1daaed12e54287beb104f04b3faaf
 F aclocal.m4 a5c22d164aff7ed549d53a90fa56d56955281f50
@@ -401,7 +401,7 @@ F ext/userauth/userauth.c 3410be31283abba70255d71fd24734e017a4497f
 F install-sh 9d4de14ab9fb0facae2f48780b874848cbf2f895 x
 F ltmain.sh 3ff0879076df340d2e23ae905484d8c15d5fdea8
 F magic.txt 8273bf49ba3b0c8559cb2774495390c31fd61c60
-F main.mk 50bac9920024b5485f06398b3980f09e97ab28cd4b5b6dcd829d2a5e3ce22e7a
+F main.mk b5f569262e4f8111bb8cf6110784b8210fe14ea45f6c7ea50fb4230ebe7a4880
 F mkso.sh fd21c06b063bb16a5d25deea1752c2da6ac3ed83
 F mptest/config01.test 3c6adcbc50b991866855f1977ff172eb6d901271
 F mptest/config02.test 4415dfe36c48785f751e16e32c20b077c28ae504
@@ -420,8 +420,8 @@ F src/auth.c 6277d63837357549fe14e723490d6dc1a38768d71c795c5eb5c0f8a99f918f73
 F src/backup.c faf17e60b43233c214aae6a8179d24503a61e83b
 F src/bitvec.c 17ea48eff8ba979f1f5b04cc484c7bb2be632f33
 F src/btmutex.c 0e9ce2d56159b89b9bc8e197e023ee11e39ff8ca
-F src/btree.c b83a6b03f160528020bb965f0c3a40af5286cd4923c3870fd218177f03a120a7
-F src/btree.h 32ef5d3f25dc70ef1ee9cecf84a023c21378f06a57cd701d2e866e141b150f09
+F src/btree.c 0a1f63b50ab1ac5d4b1637c30cb1ae123fbc162ec8cb6336ddb9491a0bc1e363
+F src/btree.h 0866c0a08255142ea0e754aabd211c843cab32045c978a592a43152405ed0c84
 F src/btreeInt.h 55b702efce17e5d1941865464227d3802cfc9c7c832fac81d4c94dced47a71fc
 F src/build.c a03eb5a1cfff74784c24a4478ba5455711571936f1ac9d43f94fa7df57509977
 F src/callback.c fe677cb5f5abb02f7a772a62a98c2f516426081df68856e8f2d5f950929b966a
@@ -431,10 +431,10 @@ F src/date.c ebe1dc7c8a347117bb02570f1a931c62dd78f4a2b1b516f4837d45b7d6426957
 F src/dbpage.c 8db4c97f630e7d83f884ea75caf1ffd0988c160e9d530194d93721c80821e0f6
 F src/dbstat.c 7a4ba8518b6369ef3600c49cf9c918ad979acba610b2aebef1b656d649b96720
 F src/delete.c 74667ad914ac143731a444a1bacf29ceb18f6eded8a0dd17aafae80baa07f8bb
-F src/expr.c f03666d7f50caf4139eb777085833808028e8af6b6dfafa722b3e843a369a126
+F src/expr.c ad6e7a9c34a4bab9d10cc857d647ae7ce370a633b5c0bfa71f1c29b81ae364b8
 F src/fault.c 460f3e55994363812d9d60844b2a6de88826e007
 F src/fkey.c d617daf66b5515e2b42c1405b2b4984c30ca50fb705ab164271a9bf66c69e331
-F src/func.c 0fb9a2d678d3c8aba89b46468b309cd7e8fa9806a369a30aa89024660845bb13
+F src/func.c 697a3ee3b8c8481db497226e9e71935727d6a9fb3d3cc049e82a1c717a0a8342
 F src/global.c ac3094f1dc59fbeb919aef7cc0cc827a8459d1fb1adb7972ef75bd9e0c10b75b
 F src/hash.c a12580e143f10301ed5166ea4964ae2853d3905a511d4e0c44497245c7ce1f7a
 F src/hash.h ab34c5c54a9e9de2e790b24349ba5aab3dbb4fd4
@@ -483,7 +483,7 @@ F src/shell.c.in f3ec8f90dd698ea98781a90642c91eacbc24f4e55bb551c7b2762000d3ef55d
 F src/sqlite.h.in b4dc75265ed04b98e2184011a7dd0054ce2137ff84867a6be8b4f3bdfbc03d30
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h c02d628cca67f3889c689d82d25c3eb45e2c155db08e4c6089b5840d64687d34
-F src/sqliteInt.h 394655443ab2ee9bde2c2f629bd1e613d5ee211dd6c16995f68e6014bbe60b5d
+F src/sqliteInt.h fd8702c65994d7de3e2d8f7d85d958731da1ed29476571fdfa2290fd8ec0bf80
 F src/sqliteLimit.h 1513bfb7b20378aa0041e7022d04acb73525de35b80b252f1b83fedb4de6a76b
 F src/status.c 9737ed017279a9e0c5da748701c3c7bf1e8ae0dae459aad20dd64fcff97a7e35
 F src/table.c b46ad567748f24a326d9de40e5b9659f96ffff34
@@ -503,7 +503,7 @@ F src/test_backup.c bf5da90c9926df0a4b941f2d92825a01bbe090a0
 F src/test_bestindex.c 78809f11026f18a93fcfd798d9479cba37e1201c830260bf1edc674b2fa9b857
 F src/test_blob.c ae4a0620b478548afb67963095a7417cd06a4ec0a56adb453542203bfdcb31ce
 F src/test_btree.c 8b2dc8b8848cf3a4db93f11578f075e82252a274
-F src/test_config.c 3904a8682aac58b77d20ca236face2b11e50781be4116004ba1ba79f69896ec9
+F src/test_config.c cc8a1d44648d9392a14f4ecfc841d027daaf61f952b9f70792edf11373aaa3dd
 F src/test_delete.c e2fe07646dff6300b48d49b2fee2fe192ed389e834dd635e3b3bac0ce0bf9f8f
 F src/test_demovfs.c a0c3bdd45ed044115c2c9f7779e56eafff18741e
 F src/test_devsym.c 1960abbb234b97e9b920f07e99503fc04b443f62bbc3c6ff2c2cea2133e3b8a2
@@ -547,7 +547,7 @@ F src/update.c 961bd1265d4d1e5cd65c9a54fa5122fb7aefcb003fcf2de0c092fceb7e58972c
 F src/utf.c 810fbfebe12359f10bc2a011520a6e10879ab2a163bcb26c74768eab82ea62a5
 F src/util.c 7315e97a8dc2c8e19ca64196c652cf0a65d13fd0a211b2cec082062372dc6261
 F src/vacuum.c 90839322fd5f00df9617eb21b68beda9b6e2a2937576b0d65985e4aeb1c53739
-F src/vdbe.c e0a1ca7539d7071d5fa582bdf27195a51197b5ae1ab0f143888b1561df592fd0
+F src/vdbe.c c70267613df80345ed9bbd9c249c365b53bb9cbbe9d3e78e6d5c049d00ef5501
 F src/vdbe.h d50cadf12bcf9fb99117ef392ce1ea283aa429270481426b6e8b0280c101fd97
 F src/vdbeInt.h 1fe00770144c12c4913128f35262d11527ef3284561baaab59b947a41c08d0d9
 F src/vdbeapi.c 9c670ca0dcc1cd86373aa353b747b26fe531ca5cd4331690c611d1f03842e2a1
@@ -561,7 +561,7 @@ F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
 F src/wal.c 5a3f464edd64596f601683ed321d12e6fd93c5fb9afdfb3653d6ffd0fee9c48f
 F src/wal.h 8de5d2d3de0956d6f6cb48c83a4012d5f227b8fe940f3a349a4b7e85ebcb492a
 F src/walker.c da987a20d40145c0a03c07d8fefcb2ed363becc7680d0500d9c79915591f5b1f
-F src/where.c 5876c9100b622f7b9e5ee7f579b8b6a71ae5ba627724cea4546d9114c32b3cb5
+F src/where.c 36b92103f726609cc3dbe07c619426bd6886bede455de56ccff54c8e567f5582
 F src/whereInt.h 82c04c5075308abbac59180c8bad5ecb45b07453981f60a53f3c7dee21e1e971
 F src/wherecode.c af1e79154aaa88cd802d6f2e5b945f67eaca7c958d1525fbf8ee19d5bd7b9020
 F src/whereexpr.c 427ea8e96ec24f2a7814c67b8024ad664a9c7656264c4566c34743cb23186e46
@@ -917,6 +917,7 @@ F test/func2.test 772d66227e4e6684b86053302e2d74a2500e1e0f
 F test/func3.test d202a7606d23f90988a664e88e268aed1087c11c
 F test/func4.test 6beacdfcb0e18c358e6c2dcacf1b65d1fa80955f
 F test/func5.test cdd224400bc3e48d891827cc913a57051a426fa4
+F test/func6.test 1a2bc511fedb779e2bd3154361385216c6d35080f36bfe896b8cdd1b1954294a
 F test/fuzz-oss1.test e58330d01cbbd8215ee636b17a03fe220b37dbfa
 F test/fuzz.test 96083052bf5765e4518c1ba686ce2bab785670d1
 F test/fuzz2.test 76dc35b32b6d6f965259508508abce75a6c4d7e1
@@ -1687,7 +1688,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 0fdf97efe5df745510c6b4b377a8ee5683a3a237630bfbd0f56e57c7c6e5b246
-R 9fe2cb7c2c9b946d64749c1df6cc4954
+P f4349c0c26611de8a7d5beb99431a575cf531cdeb0ca2413efabcf0a61e6f424 9406c0a685fd5ff3516a66402b0514a1440652822a5eecf0b7af85929f3079e8
+R 35346abc344e9d51558b9d8d5c8f2d13
+T +closed 9406c0a685fd5ff3516a66402b0514a1440652822a5eecf0b7af85929f3079e8
 U drh
-Z 157cf27648c17a2b2af97b1730aa1c08
+Z b5b643a0e7da393bb8589918154fc3c1
diff --git a/manifest.uuid b/manifest.uuid
index 3c028df06d..1c26686ec7 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-f4349c0c26611de8a7d5beb99431a575cf531cdeb0ca2413efabcf0a61e6f424
\ No newline at end of file
+4f1f1f521ae6da96b899e10bfeff6bc1ab7a45de0705076febaae20b441f48c6
\ No newline at end of file
diff --git a/src/btree.c b/src/btree.c
index 0fa00a2e12..8cd5ee6739 100644
--- a/src/btree.c
+++ b/src/btree.c
@@ -4432,6 +4432,20 @@ i64 sqlite3BtreeIntegerKey(BtCursor *pCur){
   return pCur->info.nKey;
 }
 
+#ifdef SQLITE_ENABLE_OFFSET_SQL_FUNC
+/*
+** Return the offset into the database file for the start of the
+** payload to which the cursor is pointing.
+*/
+i64 sqlite3BtreeOffset(BtCursor *pCur){
+  assert( cursorHoldsMutex(pCur) );
+  assert( pCur->eState==CURSOR_VALID );
+  getCellInfo(pCur);
+  return (i64)pCur->pBt->pageSize*((i64)pCur->pPage->pgno - 1) +
+         (i64)(pCur->info.pPayload - pCur->pPage->aData);
+}
+#endif /* SQLITE_ENABLE_OFFSET_SQL_FUNC */
+
 /*
 ** Return the number of bytes of payload for the entry that pCur is
 ** currently pointing to.  For table btrees, this will be the amount
diff --git a/src/btree.h b/src/btree.h
index e2c271cdc5..e8e114bd2a 100644
--- a/src/btree.h
+++ b/src/btree.h
@@ -291,6 +291,9 @@ int sqlite3BtreeNext(BtCursor*, int flags);
 int sqlite3BtreeEof(BtCursor*);
 int sqlite3BtreePrevious(BtCursor*, int flags);
 i64 sqlite3BtreeIntegerKey(BtCursor*);
+#ifdef SQLITE_ENABLE_OFFSET_SQL_FUNC
+i64 sqlite3BtreeOffset(BtCursor*);
+#endif
 int sqlite3BtreePayload(BtCursor*, u32 offset, u32 amt, void*);
 const void *sqlite3BtreePayloadFetch(BtCursor*, u32 *pAmt);
 u32 sqlite3BtreePayloadSize(BtCursor*);
diff --git a/src/expr.c b/src/expr.c
index 1592f10408..32cc4423fa 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -3870,9 +3870,21 @@ int sqlite3ExprCodeTarget(Parse *pParse, Expr *pExpr, int target){
         if( !pColl ) pColl = db->pDfltColl; 
         sqlite3VdbeAddOp4(v, OP_CollSeq, 0, 0, 0, (char *)pColl, P4_COLLSEQ);
       }
-      sqlite3VdbeAddOp4(v, pParse->iSelfTab ? OP_PureFunc0 : OP_Function0,
-                        constMask, r1, target, (char*)pDef, P4_FUNCDEF);
-      sqlite3VdbeChangeP5(v, (u8)nFarg);
+#ifdef SQLITE_ENABLE_OFFSET_SQL_FUNC
+      if( pDef->funcFlags & SQLITE_FUNC_OFFSET ){
+        Expr *pArg = pFarg->a[0].pExpr;
+        if( pArg->op==TK_COLUMN ){
+          sqlite3VdbeAddOp3(v, OP_Offset, pArg->iTable, pArg->iColumn, target);
+        }else{
+          sqlite3VdbeAddOp2(v, OP_Null, 0, target);
+        }
+      }else
+#endif
+      {
+        sqlite3VdbeAddOp4(v, pParse->iSelfTab ? OP_PureFunc0 : OP_Function0,
+                          constMask, r1, target, (char*)pDef, P4_FUNCDEF);
+        sqlite3VdbeChangeP5(v, (u8)nFarg);
+      }
       if( nFarg && constMask==0 ){
         sqlite3ReleaseTempRange(pParse, r1, nFarg);
       }
diff --git a/src/func.c b/src/func.c
index 7528fa8b4d..4758b0191d 100644
--- a/src/func.c
+++ b/src/func.c
@@ -1798,6 +1798,11 @@ void sqlite3RegisterBuiltinFunctions(void){
     FUNCTION2(likely,            1, 0, 0, noopFunc,  SQLITE_FUNC_UNLIKELY),
 #ifdef SQLITE_DEBUG
     FUNCTION2(affinity,          1, 0, 0, noopFunc,  SQLITE_FUNC_AFFINITY),
+#endif
+#ifdef SQLITE_ENABLE_OFFSET_SQL_FUNC
+    FUNCTION2(sqlite_unsupported_offset,
+                                 1, 0, 0, noopFunc,  SQLITE_FUNC_OFFSET|
+                                                     SQLITE_FUNC_TYPEOF),
 #endif
     FUNCTION(ltrim,              1, 1, 0, trimFunc         ),
     FUNCTION(ltrim,              2, 1, 0, trimFunc         ),
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index b11b5a8ada..8e79133200 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -1629,6 +1629,7 @@ struct FuncDestructor {
 #define SQLITE_FUNC_SLOCHNG  0x2000 /* "Slow Change". Value constant during a
                                     ** single query - might change over time */
 #define SQLITE_FUNC_AFFINITY 0x4000 /* Built-in affinity() function */
+#define SQLITE_FUNC_OFFSET   0x8000 /* Built-in sqlite_offset() function */
 
 /*
 ** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
diff --git a/src/test_config.c b/src/test_config.c
index 24a7287da2..ad63016baf 100644
--- a/src/test_config.c
+++ b/src/test_config.c
@@ -160,6 +160,12 @@ static void set_options(Tcl_Interp *interp){
   Tcl_SetVar2(interp, "sqlite_options", "mem5", "0", TCL_GLOBAL_ONLY);
 #endif
 
+#ifdef SQLITE_ENABLE_OFFSET_SQL_FUNC
+  Tcl_SetVar2(interp, "sqlite_options", "offset_sql_func","1",TCL_GLOBAL_ONLY);
+#else
+  Tcl_SetVar2(interp, "sqlite_options", "offset_sql_func","0",TCL_GLOBAL_ONLY);
+#endif
+
 #ifdef SQLITE_ENABLE_PREUPDATE_HOOK
   Tcl_SetVar2(interp, "sqlite_options", "preupdate", "1", TCL_GLOBAL_ONLY);
 #else
diff --git a/src/vdbe.c b/src/vdbe.c
index 1005560562..4d643d7266 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -2349,6 +2349,36 @@ case OP_IfNullRow: {         /* jump */
   break;
 }
 
+#ifdef SQLITE_ENABLE_OFFSET_SQL_FUNC
+/* Opcode: Offset P1 P2 P3 * *
+** Synopsis: r[P3] = sqlite_offset(P1)
+**
+** Store in register r[P3] the byte offset into the database file that is the
+** start of the payload for the record at which that cursor P1 is currently
+** pointing.
+**
+** P2 is the column number for the argument to the sqlite_offset() function.
+** This opcode does not use P2 itself, but the P2 value is used by the
+** code generator.  The P1, P2, and P3 operands to this opcode are the
+** as as for OP_Column.
+**
+** This opcode is only available if SQLite is compiled with the
+** -DSQLITE_ENABLE_OFFSET_SQL_FUNC option.
+*/
+case OP_Offset: {          /* out3 */
+  VdbeCursor *pC;    /* The VDBE cursor */
+  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
+  pC = p->apCsr[pOp->p1];
+  pOut = &p->aMem[pOp->p3];
+  if( NEVER(pC==0) || pC->eCurType!=CURTYPE_BTREE ){
+    sqlite3VdbeMemSetNull(pOut);
+  }else{
+    sqlite3VdbeMemSetInt64(pOut, sqlite3BtreeOffset(pC->uc.pCursor));
+  }
+  break;
+}
+#endif /* SQLITE_ENABLE_OFFSET_SQL_FUNC */
+
 /* Opcode: Column P1 P2 P3 P4 P5
 ** Synopsis: r[P3]=PX
 **
diff --git a/src/where.c b/src/where.c
index d3aec354ba..ec53527943 100644
--- a/src/where.c
+++ b/src/where.c
@@ -5146,7 +5146,11 @@ void sqlite3WhereEnd(WhereInfo *pWInfo){
       pOp = sqlite3VdbeGetOp(v, k);
       for(; k<last; k++, pOp++){
         if( pOp->p1!=pLevel->iTabCur ) continue;
-        if( pOp->opcode==OP_Column ){
+        if( pOp->opcode==OP_Column
+#ifdef SQLITE_ENABLE_OFFSET_SQL_FUNC
+         || pOp->opcode==OP_Offset
+#endif
+        ){
           int x = pOp->p2;
           assert( pIdx->pTable==pTab );
           if( !HasRowid(pTab) ){
diff --git a/test/func6.test b/test/func6.test
new file mode 100644
index 0000000000..0d3de8ef49
--- /dev/null
+++ b/test/func6.test
@@ -0,0 +1,86 @@
+# 2017-12-16
+#
+# 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.
+#
+#*************************************************************************
+#
+# Test cases for the sqlite_unsupported_offset() function.
+#
+# Some of the tests in this file depend on the exact placement of content
+# within b-tree pages.  Such placement is at the implementations discretion,
+# and so it is possible for results to change from one release to the next.
+#
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+ifcapable !offset_sql_func {
+  finish_test
+  return
+}
+
+do_execsql_test func6-100 {
+  PRAGMA page_size=4096;
+  PRAGMA auto_vacuum=NONE;
+  CREATE TABLE t1(a,b,c,d);
+  WITH RECURSIVE c(x) AS (VALUES(1) UNION ALL SELECT x+1 FROM c WHERE x<100)
+   INSERT INTO t1(a,b,c,d) SELECT printf('abc%03x',x), x, 1000-x, NULL FROM c;
+  CREATE INDEX t1a ON t1(a);
+  CREATE INDEX t1bc ON t1(b,c);
+  CREATE TABLE t2(x TEXT PRIMARY KEY, y) WITHOUT ROWID;
+  INSERT INTO t2(x,y) SELECT a, b FROM t1;
+}
+do_execsql_test func6-110 {
+  SELECT a, sqlite_unsupported_offset(d)/4096 + 1,
+            sqlite_unsupported_offset(d)%4096 FROM t1
+   ORDER BY rowid LIMIT 2;
+} {abc001 2 4084 abc002 2 4069}
+do_execsql_test func6-120 {
+  SELECT a, typeof(sqlite_unsupported_offset(+a)) FROM t1
+   ORDER BY rowid LIMIT 2;
+} {abc001 null abc002 null}
+do_execsql_test func6-130 {
+  SELECT a, sqlite_unsupported_offset(a)/4096+1, 
+         sqlite_unsupported_offset(a)%4096
+   FROM t1
+   ORDER BY a LIMIT 2;
+} {abc001 3 4087 abc002 3 4076}
+do_execsql_test func6-140 {
+  SELECT a, sqlite_unsupported_offset(d)/4096+1, 
+         sqlite_unsupported_offset(d)%4096
+   FROM t1
+   ORDER BY a LIMIT 2;
+} {abc001 2 4084 abc002 2 4069}
+do_execsql_test func6-150 {
+  SELECT a,
+         sqlite_unsupported_offset(a)/4096+1, 
+         sqlite_unsupported_offset(a)%4096,
+         sqlite_unsupported_offset(d)/4096+1, 
+         sqlite_unsupported_offset(d)%4096
+   FROM t1
+   ORDER BY a LIMIT 2;
+} {abc001 3 4087 2 4084 abc002 3 4076 2 4069}
+do_execsql_test func6-160 {
+  SELECT b,
+         sqlite_unsupported_offset(b)/4096+1, 
+         sqlite_unsupported_offset(b)%4096,
+         sqlite_unsupported_offset(c)/4096+1, 
+         sqlite_unsupported_offset(c)%4096,
+         sqlite_unsupported_offset(d)/4096+1, 
+         sqlite_unsupported_offset(d)%4096
+   FROM t1
+   ORDER BY b LIMIT 2;
+} {1 4 4090 4 4090 2 4084 2 4 4081 4 4081 2 4069}
+
+
+do_execsql_test func6-200 {
+  SELECT y, sqlite_unsupported_offset(y)/4096+1,
+         sqlite_unsupported_offset(y)%4096
+   FROM t2
+   ORDER BY x LIMIT 2;
+} {1 5 4087 2 5 4076}
+
+finish_test