Merge in trunk enhancements.

FossilOrigin-Name: f8bbb608cbf6c245628e3d362e9181fb3dc402b1d8241bcb687caf395f63c916

13 files changed, 453 insertions, 143 deletions

diff --git a/doc/lemon.html b/doc/lemon.html
index 114526f37..f05c481d7 100644
--- a/doc/lemon.html
+++ b/doc/lemon.html
@@ -23,6 +23,26 @@ or embedded controllers.</p>
 <p>This document is an introduction to the Lemon
 parser generator.</p>
 
+<h2>Security Note</h2>
+
+<p>The language parser code created by Lemon is very robust and
+is well-suited for use in internet-facing applications that need to
+safely process maliciously crafted inputs.
+
+<p>The "lemon.exe" command-line tool itself works great when given a valid
+input grammar file and almost always gives helpful
+error messages for malformed inputs.  However,  it is possible for
+a malicious user to craft a grammar file that will cause 
+lemon.exe to crash.
+We do not see this as a problem, as lemon.exe is not intended to be used
+with hostile inputs.
+To summarize:</p>
+
+<ul>
+<li>Parser code generated by lemon &rarr; Robust and secure
+<li>The "lemon.exe" command line tool itself &rarr; Not so much
+</ul>
+
 <h2>Theory of Operation</h2>
 
 <p>The main goal of Lemon is to translate a context free grammar (CFG)
diff --git a/ext/misc/series.c b/ext/misc/series.c
index 9f80bb46c..684995f3b 100644
--- a/ext/misc/series.c
+++ b/ext/misc/series.c
@@ -33,7 +33,7 @@
 ** The generate_series "function" is really a virtual table with the
 ** following schema:
 **
-**     CREATE FUNCTION generate_series(
+**     CREATE TABLE generate_series(
 **       value,
 **       start HIDDEN,
 **       stop HIDDEN,
diff --git a/manifest b/manifest
index 792472484..83b166c1c 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Add\sinterfaces\ssqlite3_prepare_v3()\sand\ssqlite3_prepare16_v3()\swith\sthe\nextra\sprepFlags\sargument.\s\sAdd\sthe\sSQLITE_PREPARE_PERSISTENT\soption\sas\sone\nbit\sin\sthat\sargument.
-D 2017-06-01T00:54:35.692
+C Merge\sin\strunk\senhancements.
+D 2017-06-07T16:25:25.048
 F Makefile.in 1cc758ce3374a32425e4d130c2fe7b026b20de5b8843243de75f087c0a2661fb
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc 8eeb80162074004e906b53d7340a12a14c471a83743aab975947e95ce061efcc
@@ -33,7 +33,7 @@ F config.sub 9ebe4c3b3dab6431ece34f16828b594fb420da55
 F configure 1bcc61cdd063171d8945551c265e5701a770deeff77e0ad634f8d22e4e91c831 x
 F configure.ac 13f45f02e6c51dd0e347315b5401c3f047712b7f79b7f35619115c23755afcff
 F contrib/sqlitecon.tcl 210a913ad63f9f991070821e599d600bd913e0ad
-F doc/lemon.html b5a3c07d33ecb8e019ce8f7660fe2dbbad9d7977
+F doc/lemon.html 1f8b8d4c9f5cfe40e679fee279cc9eb2da8e6eb74ad406028538d7864cc4b6cb
 F doc/pager-invariants.txt 27fed9a70ddad2088750c4a2b493b63853da2710
 F doc/vfs-shm.txt e101f27ea02a8387ce46a05be2b1a902a021d37a
 F ext/README.md fd5f78013b0a2bc6f0067afb19e6ad040e89a10179b4f6f03eee58fac5f169bd
@@ -228,7 +228,7 @@ F ext/misc/regexp.c a68d25c659bd2d893cd1215667bbf75ecb9dc7d4
 F ext/misc/remember.c 8440f8d0b452c5cdefb62b57135ccd1267aa729d
 F ext/misc/rot13.c 1ac6f95f99b575907b9b09c81a349114cf9be45a
 F ext/misc/scrub.c 1c5bfb8b0cd18b602fcb55755e84abf0023ac2fb
-F ext/misc/series.c e11e534ada797d5b816d7e7a93c022306563ca35
+F ext/misc/series.c b0f5f346aca9b7ff7caaf0da2efb4ad462441abd4dcd92a460cb573b3ea2370b
 F ext/misc/sha1.c 0b9e9b855354910d3ca467bf39099d570e73db56
 F ext/misc/shathree.c fa185d7aee0ad0aca5e091b4a2db7baff11796170e5793b5de99e511a13af448
 F ext/misc/showauth.c 732578f0fe4ce42d577e1c86dc89dd14a006ab52
@@ -351,13 +351,13 @@ F src/btmutex.c 0e9ce2d56159b89b9bc8e197e023ee11e39ff8ca
 F src/btree.c 8ac6ae352c63998228718b5f11faa0da2676710898a47284de78e96cb41dca35
 F src/btree.h 3edc5329bc59534d2d15b4f069a9f54b779a7e51289e98fa481ae3c0e526a5ca
 F src/btreeInt.h a392d353104b4add58b4a59cb185f5d5693dde832c565b77d8d4c343ed98f610
-F src/build.c 4026a9c554b233e50c5e9ad46963e676cf54dd2306d952aa1eaa07a1bc9ce14f
+F src/build.c 88a8cdc11d1c081ed565aa3e795bdf9160f4556463b4c4555e9860b59dd80340
 F src/callback.c 2e76147783386374bf01b227f752c81ec872d730
 F src/complete.c a3634ab1e687055cd002e11b8f43eb75c17da23e
 F src/ctime.c 47d91a25ad8f199a71a5b1b7b169d6dd0d6e98c5719eca801568798743d1161c
 F src/date.c cc42a41c7422389860d40419a5e3bce5eaf6e7835c3ba2677751dc653550a5c7
 F src/dbstat.c 19ee7a4e89979d4df8e44cfac7a8f905ec89b77d
-F src/delete.c bc2bfc227002ebe091e7cc321f09a48e52f86e1cd5ff9b028009db0671556749
+F src/delete.c 3213547e97b676c6fa79948b7a9ede4801ea04a01a2043241deafedf132ecf5d
 F src/expr.c 452c6f3aa656aabf3eefe96bb5f316b2c987fbc12c647964e4ed880f193ca31f
 F src/fault.c 460f3e55994363812d9d60844b2a6de88826e007
 F src/fkey.c db65492ae549c3b548c9ef1f279ce1684f1c473b116e1c56a90878cd5dcf968d
@@ -367,7 +367,7 @@ F src/hash.c 63d0ee752a3b92d4695b2b1f5259c4621b2cfebd
 F src/hash.h ab34c5c54a9e9de2e790b24349ba5aab3dbb4fd4
 F src/hwtime.h 747c1bbe9df21a92e9c50f3bbec1de841dc5e5da
 F src/in-operator.md 10cd8f4bcd225a32518407c2fb2484089112fd71
-F src/insert.c ea52232babcee65f1f9833d0fefc3b598662a004c19a178ef4fc0981e2f02a58
+F src/insert.c 974499a3999d339a4c1ba8ef129a988d9f136b3789e423808b38cdc19d28adbe
 F src/legacy.c e88ed13c2d531decde75d42c2e35623fb9ce3cb0
 F src/loadext.c a72909474dadce771d3669bf84bf689424f6f87d471fee898589c3ef9b2acfd9
 F src/main.c 1054e4dbb4fcca84246ed48b35164a996f5a52daa56c275157a5d583c0e2cd00
@@ -406,7 +406,7 @@ F src/random.c 80f5d666f23feb3e6665a6ce04c7197212a88384
 F src/resolve.c adf3ef9843135b1383321ad751f16f5a40c3f37925154555a3e61653d2a954e8
 F src/rowset.c 7b7e7e479212e65b723bf40128c7b36dc5afdfac
 F src/select.c d93205e43af302d9eb147fddecc956509ee9d0dde6297ee3f93c591f60f0e295
-F src/shell.c 3f761fe604174b31aacd2ea2eacef5e6fe550111d60c0d71532cc008c68cf3f3
+F src/shell.c eca7e7fe8dae859aa56e462c5b35c735976fa1e5e1d7a90fd5a32aa4615c1825
 F src/sqlite.h.in e644e75c21ab6247ebd8bca07a999d7d108fe8be00adc14d8c4b6004f1e75c34
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h 58fd0676d3111d02e62e5a35992a7d3da5d3f88753acc174f2d37b774fbbdd28
@@ -434,7 +434,7 @@ F src/test_config.c edcba290248dc18736dd814c9b95863c6762e0b35753048d8cbe5bf65f7a
 F src/test_delete.c e2fe07646dff6300b48d49b2fee2fe192ed389e834dd635e3b3bac0ce0bf9f8f
 F src/test_demovfs.c a0c3bdd45ed044115c2c9f7779e56eafff18741e
 F src/test_devsym.c 4e58dec2602d8e139ca08659f62a62450587cb58
-F src/test_fs.c e16cbe68d3b107e00a907c20a9a02629870eb69b
+F src/test_fs.c 35a2f7dd8a915900873386331386d9ba1ae1b5026d74fd20c2807bc76221f291
 F src/test_func.c a4fdab3363b436c1b12660e9362ce3f3782b7b5e
 F src/test_hexio.c 1d4469ca61ab202a1fcec6543f584d2407205e8d
 F src/test_init.c 4413c211a94b62157ca4c145b3f27c497f03c664
@@ -472,7 +472,7 @@ F src/update.c c443935c652af9365e033f756550b5032d02e1b06eb2cb890ed7511ae0c051dc
 F src/utf.c 699001c79f28e48e9bcdf8a463da029ea660540c
 F src/util.c fc081ec6f63448dcd80d3dfad35baecfa104823254a815b081a4d9fe76e1db23
 F src/vacuum.c 1fe4555cd8c9b263afb85b5b4ee3a4a4181ad569
-F src/vdbe.c cce462ad3cf1cad1944e105f773712a979e23fbe302328dc2885b0f4a612e1f6
+F src/vdbe.c 6783778df820f3e0c68289fe5d12ddd34168b0eb1acf248668fec6e2ea1012d5
 F src/vdbe.h dde459b1e8a02b8445ecfd5959f38cd5ebb6b0ad392d491d8b159ac8193d231a
 F src/vdbeInt.h ba7a9436196e693cc51532138ba9431af2716efbc1afe62b03b2724a67853764
 F src/vdbeapi.c 899d8f021c89ab348708b3a9b00b855f5ecc3c0f949a75359a61a3c621021281
@@ -488,7 +488,7 @@ F src/wal.h 06b2a0b599cc0f53ea97f497cf8c6b758c999f71
 F src/walker.c d46044e7a5842560dfe7122d93ff5145dd4a96f4d0bf5ba5910a7731b8c01e79
 F src/where.c 67f98714b07ec3c1d5e033a63d23c0fd70c24861b7b46b69b10700f22dca6ffe
 F src/whereInt.h 2a4b634d63ce488b46d4b0da8f2eaa8f9aeab202bc25ef76f007de5e3fba1f20
-F src/wherecode.c 8ad48867660519e262a401720845dc76934f86f558ec9606335fafcd7a2554f8
+F src/wherecode.c 339ee802d9d311acf0cba8b5a9a092e167ef71c3a777d4b3e57de25d193251c7
 F src/whereexpr.c a2fe3811d45af45a5c6667caabc15e01054fe6228c64e86e1f7d2ba5ef5284f9
 F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
 F test/affinity2.test a6d901b436328bd67a79b41bb0ac2663918fe3bd
@@ -925,7 +925,7 @@ F test/json102.test eeb54efa221e50b74a2d6fb9259963b48d7414dca3ce2fdfdeed45cb2848
 F test/json103.test c5f6b85e69de05f6b3195f9f9d5ce9cd179099a0
 F test/json104.test 877d5845f6303899b7889ea5dd1bea99076e3100574d5c536082245c5805dcaa
 F test/keyword1.test 37ef6bba5d2ed5b07ecdd6810571de2956599dff
-F test/kvtest.c b9a9822dda05a1aa481215a52e2fc93cd8b22ee5
+F test/kvtest.c d2b8cfc91047ebf6cac4f3a04f19c3a864e4ecfd683bbb65c395df450b8dc79c
 F test/lastinsert.test 42e948fd6442f07d60acbd15d33fb86473e0ef63
 F test/laststmtchanges.test ae613f53819206b3222771828d024154d51db200
 F test/like.test 0603f4fa0dad50987f70032c05800cbfa8985302
@@ -1416,7 +1416,7 @@ F test/vtabC.test 4528f459a13136f982e75614d120aef165f17292
 F test/vtabD.test 05b3f1d77117271671089e48719524b676842e96
 F test/vtabE.test d5024aa42754962f6bb0afd261681686488e7afe
 F test/vtabF.test 1918844c7c902f6a16c8dacf1ec8f84886d6e78b
-F test/vtabH.test 5f9253eb9e41ba9fe94f4aa3e9230191893d7764
+F test/vtabH.test 26d54e8b5407f797638b787a55f9c88323850a58dd142de02d06b9a1159bd283
 F test/vtabI.test 751b07636700dbdea328e4265b6077ccd6811a3f
 F test/vtab_alter.test 9e374885248f69e251bdaacf480b04a197f125e5
 F test/vtab_err.test 0d4d8eb4def1d053ac7c5050df3024fd47a3fbd8
@@ -1582,10 +1582,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P c26cf978eead1c9d265eddabaa421e7735b472fcf2792cd2bdeb0901bcf3fb44
-R 920bebc856e573465ecc651ded3907f5
-T *branch * prepare_v3
-T *sym-prepare_v3 *
-T -sym-trunk *
+P 4a25c5883380fe5990d8180adb58c3bdc7a3d081bc4c69cd4de3cd57074fb251 234ede26e30f20e6c33002739ed8be35dbfb5c77700bd857ff31072b9b7df347
+R 0957dad5bbe072099826cf9a4a9a3885
 U drh
-Z a2627d28422eb06f03507d6701dbaec5
+Z 6991b6c9f5798221e32381bb8967907a
diff --git a/manifest.uuid b/manifest.uuid
index 0149bb39c..da9d04a97 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-4a25c5883380fe5990d8180adb58c3bdc7a3d081bc4c69cd4de3cd57074fb251
\ No newline at end of file
+f8bbb608cbf6c245628e3d362e9181fb3dc402b1d8241bcb687caf395f63c916
\ No newline at end of file
diff --git a/src/build.c b/src/build.c
index e04406d85..c4bb0300a 100644
--- a/src/build.c
+++ b/src/build.c
@@ -939,7 +939,11 @@ void sqlite3StartTable(
   pTable->iPKey = -1;
   pTable->pSchema = db->aDb[iDb].pSchema;
   pTable->nTabRef = 1;
+#ifdef SQLITE_DEFAULT_ROWEST
+  pTable->nRowLogEst = sqlite3LogEst(SQLITE_DEFAULT_ROWEST);
+#else
   pTable->nRowLogEst = 200; assert( 200==sqlite3LogEst(1048576) );
+#endif
   assert( pParse->pNewTable==0 );
   pParse->pNewTable = pTable;
 
diff --git a/src/delete.c b/src/delete.c
index 6bb77b67b..9ffcf7e58 100644
--- a/src/delete.c
+++ b/src/delete.c
@@ -459,7 +459,7 @@ void sqlite3DeleteFrom(
         sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iEphCur, iKey, iPk, nPk);
       }else{
         /* Add the rowid of the row to be deleted to the RowSet */
-        nKey = 1;  /* OP_Seek always uses a single rowid */
+        nKey = 1;  /* OP_DeferredSeek always uses a single rowid */
         sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, iKey);
       }
     }
diff --git a/src/insert.c b/src/insert.c
index 48502b7e0..e684eaafa 100644
--- a/src/insert.c
+++ b/src/insert.c
@@ -524,6 +524,7 @@ void sqlite3Insert(
   if( pParse->nErr || db->mallocFailed ){
     goto insert_cleanup;
   }
+  dest.iSDParm = 0;  /* Suppress a harmless compiler warning */
 
   /* If the Select object is really just a simple VALUES() list with a
   ** single row (the common case) then keep that one row of values
diff --git a/src/shell.c b/src/shell.c
index 322c6e5c4..6a436da48 100644
--- a/src/shell.c
+++ b/src/shell.c
@@ -510,6 +510,18 @@ static int strlen30(const char *z){
 }
 
 /*
+** Return the length of a string in characters.  Multibyte UTF8 characters
+** count as a single character.
+*/
+static int strlenChar(const char *z){
+  int n = 0;
+  while( *z ){
+    if( (0xc0&*(z++))!=0x80 ) n++;
+  }
+  return n;
+}
+
+/*
 ** This routine reads a line of text from FILE in, stores
 ** the text in memory obtained from malloc() and returns a pointer
 ** to the text.  NULL is returned at end of file, or if malloc()
@@ -1917,9 +1929,9 @@ static int shell_callback(
             w = 0;
           }
           if( w==0 ){
-            w = strlen30(azCol[i] ? azCol[i] : "");
+            w = strlenChar(azCol[i] ? azCol[i] : "");
             if( w<10 ) w = 10;
-            n = strlen30(azArg && azArg[i] ? azArg[i] : p->nullValue);
+            n = strlenChar(azArg && azArg[i] ? azArg[i] : p->nullValue);
             if( w<n ) w = n;
           }
           if( i<ArraySize(p->actualWidth) ){
@@ -1954,8 +1966,8 @@ static int shell_callback(
         }else{
            w = 10;
         }
-        if( p->cMode==MODE_Explain && azArg[i] && strlen30(azArg[i])>w ){
-          w = strlen30(azArg[i]);
+        if( p->cMode==MODE_Explain && azArg[i] && strlenChar(azArg[i])>w ){
+          w = strlenChar(azArg[i]);
         }
         if( i==1 && p->aiIndent && p->pStmt ){
           if( p->iIndent<p->nIndent ){
diff --git a/src/test_fs.c b/src/test_fs.c
index dd590a662..8192beb99 100644
--- a/src/test_fs.c
+++ b/src/test_fs.c
@@ -545,6 +545,7 @@ static int fstreeFilter(
       zDir = zQuery;
     }
   }
+  if( nDir==0 ) nDir = 1;
 
   sqlite3_bind_text(pCsr->pStmt, 1, zDir, nDir, SQLITE_TRANSIENT);
   sqlite3_bind_text(pCsr->pStmt, 2, zRoot, nRoot, SQLITE_TRANSIENT);
diff --git a/src/vdbe.c b/src/vdbe.c
index 9a0678ced..4a412b4e5 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -2497,7 +2497,9 @@ case OP_Column: {
   pC = p->apCsr[pOp->p1];
   p2 = pOp->p2;
 
-  /* If the cursor cache is stale, bring it up-to-date */
+  /* If the cursor cache is stale (meaning it is not currently point at
+  ** the correct row) then bring it up-to-date by doing the necessary 
+  ** B-Tree seek. */
   rc = sqlite3VdbeCursorMoveto(&pC, &p2);
   if( rc ) goto abort_due_to_error;
 
@@ -5265,8 +5267,8 @@ case OP_IdxDelete: {
   break;
 }
 
-/* Opcode: Seek P1 * P3 P4 *
-** Synopsis: Move P3 to P1.rowid
+/* Opcode: DeferredSeek P1 * P3 P4 *
+** Synopsis: Move P3 to P1.rowid if needed
 **
 ** P1 is an open index cursor and P3 is a cursor on the corresponding
 ** table.  This opcode does a deferred seek of the P3 table cursor
@@ -5293,11 +5295,11 @@ case OP_IdxDelete: {
 **
 ** See also: Rowid, MakeRecord.
 */
-case OP_Seek:
-case OP_IdxRowid: {              /* out2 */
-  VdbeCursor *pC;                /* The P1 index cursor */
-  VdbeCursor *pTabCur;           /* The P2 table cursor (OP_Seek only) */
-  i64 rowid;                     /* Rowid that P1 current points to */
+case OP_DeferredSeek:
+case OP_IdxRowid: {           /* out2 */
+  VdbeCursor *pC;             /* The P1 index cursor */
+  VdbeCursor *pTabCur;        /* The P2 table cursor (OP_DeferredSeek only) */
+  i64 rowid;                  /* Rowid that P1 current points to */
 
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
   pC = p->apCsr[pOp->p1];
@@ -5323,7 +5325,7 @@ case OP_IdxRowid: {              /* out2 */
     if( rc!=SQLITE_OK ){
       goto abort_due_to_error;
     }
-    if( pOp->opcode==OP_Seek ){
+    if( pOp->opcode==OP_DeferredSeek ){
       assert( pOp->p3>=0 && pOp->p3<p->nCursor );
       pTabCur = p->apCsr[pOp->p3];
       assert( pTabCur!=0 );
diff --git a/src/wherecode.c b/src/wherecode.c
index feda45f91..7d1ea3859 100644
--- a/src/wherecode.c
+++ b/src/wherecode.c
@@ -966,10 +966,10 @@ static void codeCursorHint(
 **
 ** Normally, this is just:
 **
-**   OP_Seek $iCur $iRowid
+**   OP_DeferredSeek $iCur $iRowid
 **
 ** However, if the scan currently being coded is a branch of an OR-loop and
-** the statement currently being coded is a SELECT, then P3 of the OP_Seek
+** the statement currently being coded is a SELECT, then P3 of OP_DeferredSeek
 ** is set to iIdxCur and P4 is set to point to an array of integers
 ** containing one entry for each column of the table cursor iCur is open 
 ** on. For each table column, if the column is the i'th column of the 
@@ -988,7 +988,7 @@ static void codeDeferredSeek(
   assert( iIdxCur>0 );
   assert( pIdx->aiColumn[pIdx->nColumn-1]==-1 );
   
-  sqlite3VdbeAddOp3(v, OP_Seek, iIdxCur, 0, iCur);
+  sqlite3VdbeAddOp3(v, OP_DeferredSeek, iIdxCur, 0, iCur);
   if( (pWInfo->wctrlFlags & WHERE_OR_SUBCLAUSE)
    && DbMaskAllZero(sqlite3ParseToplevel(pParse)->writeMask)
   ){
diff --git a/test/kvtest.c b/test/kvtest.c
index 4fa733f1a..b80adfea0 100644
--- a/test/kvtest.c
+++ b/test/kvtest.c
@@ -71,14 +71,21 @@ static const char zHelp[] =
 "\n"
 "           --variance V           Randomly vary M by plus or minus V\n"
 "\n"
-"   kvtest export DBFILE DIRECTORY\n"
+"   kvtest export DBFILE DIRECTORY [--tree]\n"
 "\n"
 "        Export all the blobs in the kv table of DBFILE into separate\n"
-"        files in DIRECTORY.\n"
+"        files in DIRECTORY.  DIRECTORY is created if it does not previously\n"
+"        exist.  If the --tree option is used, then the blobs are written\n"
+"        into a hierarchy of directories, using names like 00/00/00,\n"
+"        00/00/01, 00/00/02, and so forth.  Without the --tree option, all\n"
+"        files are in the top-level directory with names like 000000, 000001,\n"
+"        000002, and so forth.\n"
 "\n"
-"   kvtest stat DBFILE\n"
+"   kvtest stat DBFILE [options]\n"
 "\n"
-"        Display summary information about DBFILE\n"
+"        Display summary information about DBFILE.  Options:\n"
+"\n"
+"           --vacuum               Run VACUUM on the database file\n"
 "\n"
 "   kvtest run DBFILE [options]\n"
 "\n"
@@ -90,12 +97,18 @@ static const char zHelp[] =
 "           --cache-size N         Database cache size\n"
 "           --count N              Read N blobs\n"
 "           --desc                 Read blobs in descending order\n"
+"           --fsync                Synchronous file writes\n"
+"           --integrity-check      Run \"PRAGMA integrity_check\" after test\n"
 "           --max-id N             Maximum blob key to use\n"
 "           --mmap N               Mmap as much as N bytes of DBFILE\n"
+"           --multitrans           Each read or write in its own transaction\n"
+"           --nocheckpoint         Omit the checkpoint on WAL mode writes\n"
+"           --nosync               Set \"PRAGMA synchronous=OFF\"\n"
 "           --jmode MODE           Set MODE journal mode prior to starting\n"
 "           --random               Read blobs in a random order\n"
 "           --start N              Start reading with this blob key\n"
 "           --stats                Output operating stats before exiting\n"
+"           --update               Do an overwrite test\n"
 ;
 
 /* Reference resources used */
@@ -111,6 +124,7 @@ static const char zHelp[] =
 # include <unistd.h>
 #else
   /* Provide Windows equivalent for the needed parts of unistd.h */
+# include <direct.h>
 # include <io.h>
 # define R_OK 2
 # define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)
@@ -118,6 +132,31 @@ static const char zHelp[] =
 # define access _access
 #endif
 
+#include <stdint.h>
+
+/*
+** The following macros are used to cast pointers to integers and
+** integers to pointers.  The way you do this varies from one compiler
+** to the next, so we have developed the following set of #if statements
+** to generate appropriate macros for a wide range of compilers.
+**
+** The correct "ANSI" way to do this is to use the intptr_t type.
+** Unfortunately, that typedef is not available on all compilers, or
+** if it is available, it requires an #include of specific headers
+** that vary from one machine to the next.
+**
+** Ticket #3860:  The llvm-gcc-4.2 compiler from Apple chokes on
+** the ((void*)&((char*)0)[X]) construct.  But MSVC chokes on ((void*)(X)).
+** So we have to define the macros in different ways depending on the
+** compiler.
+*/
+#if defined(__PTRDIFF_TYPE__)  /* This case should work for GCC */
+# define SQLITE_INT_TO_PTR(X)  ((void*)(__PTRDIFF_TYPE__)(X))
+# define SQLITE_PTR_TO_INT(X)  ((sqlite3_int64)(__PTRDIFF_TYPE__)(X))
+#else
+# define SQLITE_INT_TO_PTR(X)  ((void*)(intptr_t)(X))
+# define SQLITE_PTR_TO_INT(X)  ((sqlite3_int64)(intptr_t)(X))
+#endif
 
 /*
 ** Show thqe help text and quit.
@@ -201,13 +240,23 @@ static int integerValue(const char *zArg){
 /*
 ** Check the filesystem object zPath.  Determine what it is:
 **
-**    PATH_DIR     A directory
+**    PATH_DIR     A single directory holding many files
+**    PATH_TREE    A directory hierarchy with files at the leaves
 **    PATH_DB      An SQLite database
 **    PATH_NEXIST  Does not exist
 **    PATH_OTHER   Something else
+**
+** PATH_DIR means all of the separate files are grouped together
+** into a single directory with names like 000000, 000001, 000002, and
+** so forth.  PATH_TREE means there is a hierarchy of directories so
+** that no single directory has too many entries.  The files have names
+** like 00/00/00, 00/00/01, 00/00/02 and so forth.  The decision between
+** PATH_DIR and PATH_TREE is determined by the presence of a subdirectory
+** named "00" at the top-level.
 */
 #define PATH_DIR     1
-#define PATH_DB      2
+#define PATH_TREE    2
+#define PATH_DB      3
 #define PATH_NEXIST  0
 #define PATH_OTHER   99
 static int pathType(const char *zPath){
@@ -217,7 +266,15 @@ static int pathType(const char *zPath){
   memset(&x, 0, sizeof(x));
   rc = stat(zPath, &x);
   if( rc<0 ) return PATH_OTHER;
-  if( S_ISDIR(x.st_mode) ) return PATH_DIR;
+  if( S_ISDIR(x.st_mode) ){
+    char *zLayer1 = sqlite3_mprintf("%s/00", zPath);
+    memset(&x, 0, sizeof(x));
+    rc = stat(zLayer1, &x);
+    sqlite3_free(zLayer1);
+    if( rc<0 ) return PATH_DIR;
+    if( S_ISDIR(x.st_mode) ) return PATH_TREE;
+    return PATH_DIR;
+  }
   if( (x.st_size%512)==0 ) return PATH_DB;
   return PATH_OTHER;
 }
@@ -328,6 +385,7 @@ static int statMain(int argc, char **argv){
   sqlite3 *db;
   char *zSql;
   sqlite3_stmt *pStmt;
+  int doVacuum = 0;
 
   assert( strcmp(argv[1],"stat")==0 );
   assert( argc>=3 );
@@ -336,12 +394,21 @@ static int statMain(int argc, char **argv){
     char *z = argv[i];
     if( z[0]!='-' ) fatalError("unknown argument: \"%s\"", z);
     if( z[1]=='-' ) z++;
+    if( strcmp(z, "-vacuum")==0 ){
+      doVacuum = 1;
+      continue;
+    }
     fatalError("unknown option: \"%s\"", argv[i]);
   }
   rc = sqlite3_open(zDb, &db);
   if( rc ){
     fatalError("cannot open database \"%s\": %s", zDb, sqlite3_errmsg(db));
   }
+  if( doVacuum ){
+    printf("Vacuuming...."); fflush(stdout);
+    sqlite3_exec(db, "VACUUM", 0, 0, 0);
+    printf("       done\n");
+  }
   zSql = sqlite3_mprintf(
     "SELECT count(*), min(length(v)), max(length(v)), avg(length(v))"
     "  FROM kv"
@@ -374,39 +441,53 @@ static int statMain(int argc, char **argv){
     printf("Page-count:         %8d\n", sqlite3_column_int(pStmt, 0));
   }
   sqlite3_finalize(pStmt);
+  zSql = sqlite3_mprintf("PRAGMA freelist_count");
+  rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
+  if( rc ) fatalError("cannot prepare SQL [%s]: %s", zSql, sqlite3_errmsg(db));
+  sqlite3_free(zSql);
+  if( sqlite3_step(pStmt)==SQLITE_ROW ){
+    printf("Freelist-count:     %8d\n", sqlite3_column_int(pStmt, 0));
+  }
+  sqlite3_finalize(pStmt);
+  rc = sqlite3_prepare_v2(db, "PRAGMA integrity_check(10)", -1, &pStmt, 0);
+  if( rc ) fatalError("cannot prepare integrity check: %s", sqlite3_errmsg(db));
+  while( sqlite3_step(pStmt)==SQLITE_ROW ){
+    printf("Integrity-check:    %s\n", sqlite3_column_text(pStmt, 0));
+  }
+  sqlite3_finalize(pStmt);
   sqlite3_close(db);
   return 0;
 }
 
 /*
-** Implementation of the "writefile(X,Y)" SQL function.  The argument Y
-** is written into file X.  The number of bytes written is returned.  Or
-** NULL is returned if something goes wrong, such as being unable to open
-** file X for writing.
+**      remember(V,PTR)
+**
+** Return the integer value V.  Also save the value of V in a
+** C-language variable whose address is PTR.
 */
-static void writefileFunc(
-  sqlite3_context *context,
+static void rememberFunc(
+  sqlite3_context *pCtx,
   int argc,
   sqlite3_value **argv
 ){
-  FILE *out;
-  const char *z;
-  sqlite3_int64 rc;
-  const char *zFile;
-
-  zFile = (const char*)sqlite3_value_text(argv[0]);
-  if( zFile==0 ) return;
-  out = fopen(zFile, "wb");
-  if( out==0 ) return;
-  z = (const char*)sqlite3_value_blob(argv[1]);
-  if( z==0 ){
-    rc = 0;
-  }else{
-    rc = fwrite(z, 1, sqlite3_value_bytes(argv[1]), out);
-  }
-  fclose(out);
-  printf("\r%s   ", zFile); fflush(stdout);
-  sqlite3_result_int64(context, rc);
+  sqlite3_int64 v;
+  sqlite3_int64 ptr;
+  assert( argc==2 );
+  v = sqlite3_value_int64(argv[0]);
+  ptr = sqlite3_value_int64(argv[1]);
+  *(sqlite3_int64*)SQLITE_INT_TO_PTR(ptr) = v;
+  sqlite3_result_int64(pCtx, v);
+}
+
+/*
+** Make sure a directory named zDir exists.
+*/
+static void kvtest_mkdir(const char *zDir){
+#if defined(_WIN32)
+  (void)mkdir(zDir);
+#else
+  (void)mkdir(zDir, 0755);
+#endif
 }
 
 /*
@@ -416,32 +497,77 @@ static int exportMain(int argc, char **argv){
   char *zDb;
   char *zDir;
   sqlite3 *db;
-  char *zSql;
+  sqlite3_stmt *pStmt;
   int rc;
-  char *zErrMsg = 0;
+  int ePathType;
+  int nFN;
+  char *zFN;
+  char *zTail;
+  size_t nWrote;
+  int i;
 
   assert( strcmp(argv[1],"export")==0 );
   assert( argc>=3 );
+  if( argc<4 ) fatalError("Usage: kvtest export DATABASE DIRECTORY [OPTIONS]");
   zDb = argv[2];
-  if( argc!=4 ) fatalError("Usage: kvtest export DATABASE DIRECTORY");
   zDir = argv[3];
-  if( pathType(zDir)!=PATH_DIR ){
+  kvtest_mkdir(zDir);
+  for(i=4; i<argc; i++){
+    const char *z = argv[i];
+    if( z[0]=='-' && z[1]=='-' ) z++;
+    if( strcmp(z,"-tree")==0 ){
+      zFN = sqlite3_mprintf("%s/00", zDir);
+      kvtest_mkdir(zFN);
+      sqlite3_free(zFN);
+      continue;
+    }
+    fatalError("unknown argument: \"%s\"\n", argv[i]);
+  }
+  ePathType = pathType(zDir);
+  if( ePathType!=PATH_DIR && ePathType!=PATH_TREE ){
     fatalError("object \"%s\" is not a directory", zDir);
   }
   rc = sqlite3_open(zDb, &db);
   if( rc ){
     fatalError("cannot open database \"%s\": %s", zDb, sqlite3_errmsg(db));
   }
-  sqlite3_create_function(db, "writefile", 2, SQLITE_UTF8, 0,
-                          writefileFunc, 0, 0);
-  zSql = sqlite3_mprintf(
-    "SELECT writefile(printf('%s/%%06d',k),v) FROM kv;",
-    zDir
-  );
-  rc = sqlite3_exec(db, zSql, 0, 0, &zErrMsg);
-  if( rc ) fatalError("database create failed: %s", zErrMsg);
-  sqlite3_free(zSql);
+  rc = sqlite3_prepare_v2(db, "SELECT k, v FROM kv ORDER BY k", -1, &pStmt, 0);
+  if( rc ){
+    fatalError("prepare_v2 failed: %s\n", sqlite3_errmsg(db));
+  }
+  nFN = (int)strlen(zDir);
+  zFN = sqlite3_mprintf("%s/00/00/00.extra---------------------", zDir);
+  if( zFN==0 ){
+    fatalError("malloc failed\n");
+  }
+  zTail = zFN + nFN + 1;
+  while( sqlite3_step(pStmt)==SQLITE_ROW ){
+    int iKey = sqlite3_column_int(pStmt, 0);
+    sqlite3_int64 nData = sqlite3_column_bytes(pStmt, 1);
+    const void *pData = sqlite3_column_blob(pStmt, 1);
+    FILE *out;
+    if( ePathType==PATH_DIR ){
+      sqlite3_snprintf(20, zTail, "%06d", iKey);
+    }else{
+      sqlite3_snprintf(20, zTail, "%02d", iKey/10000);
+      kvtest_mkdir(zFN);
+      sqlite3_snprintf(20, zTail, "%02d/%02d", iKey/10000, (iKey/100)%100);
+      kvtest_mkdir(zFN);
+      sqlite3_snprintf(20, zTail, "%02d/%02d/%02d",
+                       iKey/10000, (iKey/100)%100, iKey%100);
+    }
+    out = fopen(zFN, "wb");      
+    nWrote = fwrite(pData, 1, nData, out);
+    fclose(out);
+    printf("\r%s   ", zTail); fflush(stdout);
+    if( nWrote!=nData ){
+      fatalError("Wrote only %d of %d bytes to %s\n",
+                  (int)nWrote, nData, zFN);
+    }
+  }
+  sqlite3_finalize(pStmt);
   sqlite3_close(db);
+  sqlite3_free(zFN);
   printf("\n");
   return 0;
 }
@@ -461,7 +587,7 @@ static int exportMain(int argc, char **argv){
 ** NULL is returned if any error is encountered. The final value of *pnByte
 ** is undefined in this case.
 */
-static unsigned char *readFile(const char *zName, int *pnByte){
+static unsigned char *readFile(const char *zName, sqlite3_int64 *pnByte){
   FILE *in;               /* FILE from which to read content of zName */
   sqlite3_int64 nIn;      /* Size of zName in bytes */
   size_t nRead;           /* Number of bytes actually read */
@@ -479,11 +605,56 @@ static unsigned char *readFile(const char *zName, int *pnByte){
     sqlite3_free(pBuf);
     return 0;
   }
-  if( pnByte ) *pnByte = (int)nIn;
+  if( pnByte ) *pnByte = nIn;
   return pBuf;
 }
 
 /*
+** Overwrite a file with randomness.  Do not change the size of the
+** file.
+*/
+static void updateFile(const char *zName, sqlite3_int64 *pnByte, int doFsync){
+  FILE *out;              /* FILE from which to read content of zName */
+  sqlite3_int64 sz;       /* Size of zName in bytes */
+  size_t nWritten;        /* Number of bytes actually read */
+  unsigned char *pBuf;    /* Content to store on disk */
+  const char *zMode = "wb";   /* Mode for fopen() */
+
+  sz = fileSize(zName);
+  if( sz<0 ){
+    fatalError("No such file: \"%s\"", zName);
+  }
+  *pnByte = sz;
+  if( sz==0 ) return;
+  pBuf = sqlite3_malloc64( sz );
+  if( pBuf==0 ){
+    fatalError("Cannot allocate %lld bytes\n", sz);
+  }
+  sqlite3_randomness((int)sz, pBuf); 
+#if defined(_WIN32)
+  if( doFsync ) zMode = "wbc";
+#endif
+  out = fopen(zName, zMode);
+  if( out==0 ){
+    fatalError("Cannot open \"%s\" for writing\n", zName);
+  }
+  nWritten = fwrite(pBuf, 1, (size_t)sz, out);
+  if( doFsync ){
+#if defined(_WIN32)
+    fflush(out);
+#else
+    fsync(fileno(out));
+#endif
+  }
+  fclose(out);
+  if( nWritten!=(size_t)sz ){
+    fatalError("Wrote only %d of %d bytes to \"%s\"\n",
+               (int)nWritten, (int)sz, zName);
+  }
+  sqlite3_free(pBuf);
+}
+
+/*
 ** Return the current time in milliseconds since the beginning of
 ** the Julian epoch.
 */
@@ -637,16 +808,22 @@ static int runMain(int argc, char **argv){
   int bBlobApi = 0;           /* Use the incremental blob I/O API */
   int bStats = 0;             /* Print stats before exiting */
   int eOrder = ORDER_ASC;     /* Access order */
+  int isUpdateTest = 0;       /* Do in-place updates rather than reads */
+  int doIntegrityCk = 0;      /* Run PRAGMA integrity_check after the test */
+  int noSync = 0;             /* Disable synchronous mode */
+  int doFsync = 0;            /* Update disk files synchronously */
+  int doMultiTrans = 0;       /* Each operation in its own transaction */
+  int noCheckpoint = 0;       /* Omit the checkpoint in WAL mode */
   sqlite3 *db = 0;            /* Database connection */
   sqlite3_stmt *pStmt = 0;    /* Prepared statement for SQL access */
   sqlite3_blob *pBlob = 0;    /* Handle for incremental Blob I/O */
   sqlite3_int64 tmStart;      /* Start time */
   sqlite3_int64 tmElapsed;    /* Elapsed time */
   int mmapSize = 0;           /* --mmap N argument */
-  int nData = 0;              /* Bytes of data */
+  sqlite3_int64 nData = 0;    /* Bytes of data */
   sqlite3_int64 nTotal = 0;   /* Total data read */
   unsigned char *pData = 0;   /* Content of the blob */
-  int nAlloc = 0;             /* Space allocated for pData[] */
+  sqlite3_int64 nAlloc = 0;   /* Space allocated for pData[] */
   const char *zJMode = 0;     /* Journal mode */
   
 
@@ -660,12 +837,42 @@ static int runMain(int argc, char **argv){
     char *z = argv[i];
     if( z[0]!='-' ) fatalError("unknown argument: \"%s\"", z);
     if( z[1]=='-' ) z++;
+    if( strcmp(z, "-asc")==0 ){
+      eOrder = ORDER_ASC;
+      continue;
+    }
+    if( strcmp(z, "-blob-api")==0 ){
+      bBlobApi = 1;
+      continue;
+    }
+    if( strcmp(z, "-cache-size")==0 ){
+      if( i==argc-1 ) fatalError("missing argument on \"%s\"", argv[i]);
+      iCache = integerValue(argv[++i]);
+      continue;
+    }
     if( strcmp(z, "-count")==0 ){
       if( i==argc-1 ) fatalError("missing argument on \"%s\"", argv[i]);
       nCount = integerValue(argv[++i]);
       if( nCount<1 ) fatalError("the --count must be positive");
       continue;
     }
+    if( strcmp(z, "-desc")==0 ){
+      eOrder = ORDER_DESC;
+      continue;
+    }
+    if( strcmp(z, "-fsync")==0 ){
+      doFsync = 1;
+      continue;
+    }
+    if( strcmp(z, "-integrity-check")==0 ){
+      doIntegrityCk = 1;
+      continue;
+    }
+    if( strcmp(z, "-jmode")==0 ){
+      if( i==argc-1 ) fatalError("missing argument on \"%s\"", argv[i]);
+      zJMode = argv[++i];
+      continue;
+    }
     if( strcmp(z, "-mmap")==0 ){
       if( i==argc-1 ) fatalError("missing argument on \"%s\"", argv[i]);
       mmapSize = integerValue(argv[++i]);
@@ -677,44 +884,45 @@ static int runMain(int argc, char **argv){
       iMax = integerValue(argv[++i]);
       continue;
     }
-    if( strcmp(z, "-start")==0 ){
-      if( i==argc-1 ) fatalError("missing argument on \"%s\"", argv[i]);
-      iKey = integerValue(argv[++i]);
-      if( iKey<1 ) fatalError("the --start must be positive");
+    if( strcmp(z, "-multitrans")==0 ){
+      doMultiTrans = 1;
       continue;
     }
-    if( strcmp(z, "-cache-size")==0 ){
-      if( i==argc-1 ) fatalError("missing argument on \"%s\"", argv[i]);
-      iCache = integerValue(argv[++i]);
+    if( strcmp(z, "-nocheckpoint")==0 ){
+      noCheckpoint = 1;
       continue;
     }
-    if( strcmp(z, "-jmode")==0 ){
-      if( i==argc-1 ) fatalError("missing argument on \"%s\"", argv[i]);
-      zJMode = argv[++i];
+    if( strcmp(z, "-nosync")==0 ){
+      noSync = 1;
       continue;
     }
     if( strcmp(z, "-random")==0 ){
       eOrder = ORDER_RANDOM;
       continue;
     }
-    if( strcmp(z, "-asc")==0 ){
-      eOrder = ORDER_ASC;
-      continue;
-    }
-    if( strcmp(z, "-desc")==0 ){
-      eOrder = ORDER_DESC;
-      continue;
-    }
-    if( strcmp(z, "-blob-api")==0 ){
-      bBlobApi = 1;
+    if( strcmp(z, "-start")==0 ){
+      if( i==argc-1 ) fatalError("missing argument on \"%s\"", argv[i]);
+      iKey = integerValue(argv[++i]);
+      if( iKey<1 ) fatalError("the --start must be positive");
       continue;
     }
     if( strcmp(z, "-stats")==0 ){
       bStats = 1;
       continue;
     }
+    if( strcmp(z, "-update")==0 ){
+      isUpdateTest = 1;
+      continue;
+    }
     fatalError("unknown option: \"%s\"", argv[i]);
   }
+  if( eType==PATH_DB ){
+    /* Recover any prior crashes prior to starting the timer */
+    sqlite3_open(zDb, &db);
+    sqlite3_exec(db, "SELECT rowid FROM sqlite_master LIMIT 1", 0, 0, 0);
+    sqlite3_close(db);
+    db = 0;
+  }
   tmStart = timeOfDay();
   if( eType==PATH_DB ){
     char *zSql;
@@ -724,9 +932,13 @@ static int runMain(int argc, char **argv){
     }
     zSql = sqlite3_mprintf("PRAGMA mmap_size=%d", mmapSize);
     sqlite3_exec(db, zSql, 0, 0, 0);
+    sqlite3_free(zSql);
     zSql = sqlite3_mprintf("PRAGMA cache_size=%d", iCache);
     sqlite3_exec(db, zSql, 0, 0, 0);
     sqlite3_free(zSql);
+    if( noSync ){
+      sqlite3_exec(db, "PRAGMA synchronous=OFF", 0, 0, 0);
+    }
     pStmt = 0;
     sqlite3_prepare_v2(db, "PRAGMA page_size", -1, &pStmt, 0);
     if( sqlite3_step(pStmt)==SQLITE_ROW ){
@@ -745,6 +957,9 @@ static int runMain(int argc, char **argv){
       zSql = sqlite3_mprintf("PRAGMA journal_mode=%Q", zJMode);
       sqlite3_exec(db, zSql, 0, 0, 0);
       sqlite3_free(zSql);
+      if( noCheckpoint ){
+        sqlite3_exec(db, "PRAGMA wal_autocheckpoint=0", 0, 0, 0);
+      }
     }
     sqlite3_prepare_v2(db, "PRAGMA journal_mode", -1, &pStmt, 0);
     if( sqlite3_step(pStmt)==SQLITE_ROW ){
@@ -761,22 +976,32 @@ static int runMain(int argc, char **argv){
       sqlite3_finalize(pStmt);
     }
     pStmt = 0;
-    sqlite3_exec(db, "BEGIN", 0, 0, 0);
+    if( !doMultiTrans ) sqlite3_exec(db, "BEGIN", 0, 0, 0);
   }
   if( iMax<=0 ) iMax = 1000;
   for(i=0; i<nCount; i++){
-    if( eType==PATH_DIR ){
-      /* CASE 1: Reading blobs out of separate files */
+    if( eType==PATH_DIR || eType==PATH_TREE ){
+      /* CASE 1: Reading or writing blobs out of separate files */
       char *zKey;
-      zKey = sqlite3_mprintf("%s/%06d", zDb, iKey);
+      if( eType==PATH_DIR ){
+        zKey = sqlite3_mprintf("%s/%06d", zDb, iKey);
+      }else{
+        zKey = sqlite3_mprintf("%s/%02d/%02d/%02d", zDb, iKey/10000,
+                               (iKey/100)%100, iKey%100);
+      }
       nData = 0;
-      pData = readFile(zKey, &nData);
+      if( isUpdateTest ){
+        updateFile(zKey, &nData, doFsync);
+      }else{
+        pData = readFile(zKey, &nData);
+        sqlite3_free(pData);
+      }
       sqlite3_free(zKey);
-      sqlite3_free(pData);
     }else if( bBlobApi ){
       /* CASE 2: Reading from database using the incremental BLOB I/O API */
       if( pBlob==0 ){
-        rc = sqlite3_blob_open(db, "main", "kv", "v", iKey, 0, &pBlob);
+        rc = sqlite3_blob_open(db, "main", "kv", "v", iKey,
+                               isUpdateTest, &pBlob);
         if( rc ){
           fatalError("could not open sqlite3_blob handle: %s",
                      sqlite3_errmsg(db));
@@ -788,20 +1013,39 @@ static int runMain(int argc, char **argv){
         nData = sqlite3_blob_bytes(pBlob);
         if( nAlloc<nData+1 ){
           nAlloc = nData+100;
-          pData = sqlite3_realloc(pData, nAlloc);
+          pData = sqlite3_realloc64(pData, nAlloc);
         }
         if( pData==0 ) fatalError("cannot allocate %d bytes", nData+1);
-        rc = sqlite3_blob_read(pBlob, pData, nData, 0);
-        if( rc!=SQLITE_OK ){
-          fatalError("could not read the blob at %d: %s", iKey,
-                     sqlite3_errmsg(db));
+        if( isUpdateTest ){
+          sqlite3_randomness((int)nData, pData);
+          rc = sqlite3_blob_write(pBlob, pData, (int)nData, 0);
+          if( rc!=SQLITE_OK ){
+            fatalError("could not write the blob at %d: %s", iKey,
+                      sqlite3_errmsg(db));
+          }
+        }else{
+          rc = sqlite3_blob_read(pBlob, pData, (int)nData, 0);
+          if( rc!=SQLITE_OK ){
+            fatalError("could not read the blob at %d: %s", iKey,
+                      sqlite3_errmsg(db));
+          }
         }
       }
     }else{
       /* CASE 3: Reading from database using SQL */
       if( pStmt==0 ){
-        rc = sqlite3_prepare_v2(db, 
-               "SELECT v FROM kv WHERE k=?1", -1, &pStmt, 0);
+        if( isUpdateTest ){
+          sqlite3_create_function(db, "remember", 2, SQLITE_UTF8, 0,
+                                  rememberFunc, 0, 0);
+
+          rc = sqlite3_prepare_v2(db, 
+            "UPDATE kv SET v=randomblob(remember(length(v),?2))"
+            " WHERE k=?1", -1, &pStmt, 0);
+          sqlite3_bind_int64(pStmt, 2, SQLITE_PTR_TO_INT(&nData));
+        }else{
+          rc = sqlite3_prepare_v2(db, 
+                 "SELECT v FROM kv WHERE k=?1", -1, &pStmt, 0);
+        }
         if( rc ){
           fatalError("cannot prepare query: %s", sqlite3_errmsg(db));
         }
@@ -809,12 +1053,11 @@ static int runMain(int argc, char **argv){
         sqlite3_reset(pStmt);
       }
       sqlite3_bind_int(pStmt, 1, iKey);
+      nData = 0;
       rc = sqlite3_step(pStmt);
       if( rc==SQLITE_ROW ){
         nData = sqlite3_column_bytes(pStmt, 0);
         pData = (unsigned char*)sqlite3_column_blob(pStmt, 0);
-      }else{
-        nData = 0;
       }
     }
     if( eOrder==ORDER_ASC ){
@@ -835,13 +1078,33 @@ static int runMain(int argc, char **argv){
   if( bStats ){
     display_stats(db, 0);
   }
-  if( db ) sqlite3_close(db);
+  if( db ){
+    if( !doMultiTrans ) sqlite3_exec(db, "COMMIT", 0, 0, 0);
+    if( !noCheckpoint ){
+      sqlite3_close(db);
+      db = 0;
+    }
+  }
   tmElapsed = timeOfDay() - tmStart;
+  if( db && noCheckpoint ){
+    sqlite3_close(db);
+    db = 0;
+  }
   if( nExtra ){
     printf("%d cycles due to %d misses\n", nCount, nExtra);
   }
   if( eType==PATH_DB ){
     printf("SQLite version: %s\n", sqlite3_libversion());
+    if( doIntegrityCk ){
+      sqlite3_open(zDb, &db);
+      sqlite3_prepare_v2(db, "PRAGMA integrity_check", -1, &pStmt, 0);
+      while( sqlite3_step(pStmt)==SQLITE_ROW ){
+        printf("integrity-check: %s\n", sqlite3_column_text(pStmt, 0));
+      }
+      sqlite3_finalize(pStmt);
+      sqlite3_close(db);
+      db = 0;
+    }
   }
   printf("--count %d --max-id %d", nCount-nExtra, iMax);
   switch( eOrder ){
@@ -852,11 +1115,17 @@ static int runMain(int argc, char **argv){
   if( eType==PATH_DB ){
     printf("--cache-size %d --jmode %s\n", iCache, zJMode);
     printf("--mmap %d%s\n", mmapSize, bBlobApi ? " --blob-api" : "");
+    if( noSync ) printf("--nosync\n");
   }
   if( iPagesize ) printf("Database page size: %d\n", iPagesize);
   printf("Total elapsed time: %.3f\n", tmElapsed/1000.0);
-  printf("Microseconds per BLOB read: %.3f\n", tmElapsed*1000.0/nCount);
-  printf("Content read rate: %.1f MB/s\n", nTotal/(1000.0*tmElapsed));
+  if( isUpdateTest ){
+    printf("Microseconds per BLOB write: %.3f\n", tmElapsed*1000.0/nCount);
+    printf("Content write rate: %.1f MB/s\n", nTotal/(1000.0*tmElapsed));
+  }else{
+    printf("Microseconds per BLOB read: %.3f\n", tmElapsed*1000.0/nCount);
+    printf("Content read rate: %.1f MB/s\n", nTotal/(1000.0*tmElapsed));
+  }
   return 0;
 }
 
diff --git a/test/vtabH.test b/test/vtabH.test
index c5684ff51..2ebc3f9cc 100644
--- a/test/vtabH.test
+++ b/test/vtabH.test
@@ -216,24 +216,28 @@ if {$tcl_platform(platform)!="windows" || \
   } {}
 
   set pwd [pwd]
-  do_execsql_test 3.5 {
-    SELECT path, size FROM fstree WHERE path GLOB $pwd || '/subdir/*' ORDER BY 1
-  } [list \
-    "$pwd/subdir/x1.txt" 143 \
-    "$pwd/subdir/x2.txt" 153 \
-  ]
-  do_execsql_test 3.6 {
-    SELECT path, size FROM fstree WHERE path LIKE $pwd || '/subdir/%' ORDER BY 1
-  } [list \
-    "$pwd/subdir/x1.txt" 143 \
-    "$pwd/subdir/x2.txt" 153 \
-  ]
-  do_execsql_test 3.7 {
-    SELECT sum(size) FROM fstree WHERE path LIKE $pwd || '/subdir/%'
-  } 296
-  do_execsql_test 3.8 {
-    SELECT size FROM fstree WHERE path = $pwd || '/subdir/x1.txt'
-  } 143
+  if {![string match {*[_%]*} $pwd]} {
+    do_execsql_test 3.5 {
+      SELECT path, size FROM fstree 
+       WHERE path GLOB $pwd || '/subdir/*' ORDER BY 1
+    } [list \
+      "$pwd/subdir/x1.txt" 143 \
+      "$pwd/subdir/x2.txt" 153 \
+    ]
+    do_execsql_test 3.6 {
+      SELECT path, size FROM fstree
+       WHERE path LIKE $pwd || '/subdir/%' ORDER BY 1
+    } [list \
+      "$pwd/subdir/x1.txt" 143 \
+      "$pwd/subdir/x2.txt" 153 \
+    ]
+    do_execsql_test 3.7 {
+      SELECT sum(size) FROM fstree WHERE path LIKE $pwd || '/subdir/%'
+    } 296
+    do_execsql_test 3.8 {
+      SELECT size FROM fstree WHERE path = $pwd || '/subdir/x1.txt'
+    } 143
+  }
 
 }