Multiple optimizations that try to preserve or infer the zero-terminated

property of TEXT values.  Avoid unnecessary copying of text values destined
to become function parameters.  All changes help improve performance of
doing UPDATEs on large JSON values that are indexed multiple ways.

FossilOrigin-Name: d0278cdedfa04fb0b61838ab9622be8a2c462f58d5c3ebc4c5f802a727d0974e

diff --git a/manifest b/manifest
index 1eaf96f72f96578ad70c1de00d5ff57ccd38c0ca..2bf0e377ab422ca896792b2b8f27074e7e89f097 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Performance\senhancements\sto\sthe\sJSON\sparser\sand\scode\sgenerator.
-D 2023-07-19T23:02:45.962
+C Multiple\soptimizations\sthat\stry\sto\spreserve\sor\sinfer\sthe\szero-terminated\nproperty\sof\sTEXT\svalues.\s\sAvoid\sunnecessary\scopying\sof\stext\svalues\sdestined\nto\sbecome\sfunction\sparameters.\s\sAll\schanges\shelp\simprove\sperformance\sof\ndoing\sUPDATEs\son\slarge\sJSON\svalues\sthat\sare\sindexed\smultiple\sways.
+D 2023-07-21T15:01:53.046
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -587,7 +587,7 @@ F src/date.c f73f203b3877cef866c60ab402aec2bf89597219b60635cf50cbe3c5e4533e94
 F src/dbpage.c f3eea5f7ec47e09ee7da40f42b25092ecbe961fc59566b8e5f705f34335b2387
 F src/dbstat.c ec92074baa61d883de58c945162d9e666c13cd7cf3a23bc38b4d1c4d0b2c2bef
 F src/delete.c cd5f5cd06ed0b6a882ec1a8c2a0d73b3cecb28479ad19e9931c4706c5e2182be
-F src/expr.c 8d1656b65e26af3e34f78e947ac423f0d20c214ed25a67486e433bf16ca6b543
+F src/expr.c ef4a81822da6f767696bd7f4b9983328af061158958138540142285a5b1181b7
 F src/fault.c 460f3e55994363812d9d60844b2a6de88826e007
 F src/fkey.c a7fcbf7e66d14dbb73cf49f31489ebf66d0e6006c62b95246924a3bae9f37b36
 F src/func.c 25f2e0204c011be56fc3c9a180534b68ca4866c61ec19806880136450434112d
@@ -597,7 +597,7 @@ F src/hash.h 3340ab6e1d13e725571d7cee6d3e3135f0779a7d8e76a9ce0a85971fa3953c51
 F src/hwtime.h f9c2dfb84dce7acf95ce6d289e46f5f9d3d1afd328e53da8f8e9008e3b3caae6
 F src/in-operator.md 10cd8f4bcd225a32518407c2fb2484089112fd71
 F src/insert.c 3f0a94082d978bbdd33c38fefea15346c6c6bffb70bc645a71dc0f1f87dd3276
-F src/json.c e48136fce64e5004b1b8be76624cc9a4ac9ff6ae630a97df187c0ea4b9692d1b
+F src/json.c 2bf3223892b4b9be39d701a5d349efcce5f5eebf71baaf91ba5866e10127e839
 F src/legacy.c d7874bc885906868cd51e6c2156698f2754f02d9eee1bae2d687323c3ca8e5aa
 F src/loadext.c 176d6b2cb18a6ad73b133db17f6fc351c4d9a2d510deebdb76c22bde9cfd1465
 F src/main.c 512b1d45bc556edf4471a845afb7ba79e64bd5b832ab222dc195c469534cd002
@@ -707,10 +707,10 @@ F src/upsert.c 5303dc6c518fa7d4b280ec65170f465c7a70b7ac2b22491598f6d0b4875b3145
 F src/utf.c ee39565f0843775cc2c81135751ddd93eceb91a673ea2c57f61c76f288b041a0
 F src/util.c fea6fffdee3cdae917a66b70deec59d4f238057cfd6de623d15cf990c196940d
 F src/vacuum.c 604fcdaebe76f3497c855afcbf91b8fa5046b32de3045bab89cc008d68e40104
-F src/vdbe.c 74282a947234513872a83b0bab1b8c644ece64b3e27b053ef17677c8ff9c81e0
+F src/vdbe.c 4cda877d413a18fa07346b08d6959b3d18ce982357921e7acb9649fca2534a12
 F src/vdbe.h 41485521f68e9437fdb7ec4a90f9d86ab294e9bb8281e33b235915e29122cfc0
 F src/vdbeInt.h 7bd49eef8f89c1a271fbf12d80a206bf56c876814c5fc6bee340f4e1907095ae
-F src/vdbeapi.c de9703f8705afc393cc2864669ce28cf9516983c8331d59aa2b978de01634365
+F src/vdbeapi.c 1b17d1a53c3b88eb8bf2534f4f3557957f59f9431e5283734452b191cd45898d
 F src/vdbeaux.c b5e3f7e158518b4eca6f166ac43900640a3fe9735c710e12bfa119af21059339
 F src/vdbeblob.c 2516697b3ee8154eb8915f29466fb5d4f1ae39ee8b755ea909cefaf57ec5e2ce
 F src/vdbemem.c cf4a1556dd5b18c071cf7c243373c29ce752eb516022e3ad49ba72f08b785033
@@ -2043,8 +2043,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P bee9e403ae47103938aabb9a7a7e120dfa741b464875965e58788a51fa56a8fe 144c8ccf6e5bb2527dd98742f0d67e0a16c627e7c67f754ce8ed4c4fb5b8d8b6
-R af54725f832c177294e9e511cdacd53d
+P 0a745897d66e9f36ea6e787fad54f0c413d52c226dc96fad36ccd33a0aa1930e
+R ad6898efbc6819851ab380be79271f0e
 U drh
-Z 1c679f829efc53f4f55993e30939aa14
+Z ecdcb9c56dec3594bcd0055088d236ad
 # Remove this line to create a well-formed Fossil manifest.

diff --git a/manifest.uuid b/manifest.uuid
index 10f9cdd123142f17851ceda249984b922b4295a3..000a57e974c5da531569e7b39a023b25dfb2c277 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-0a745897d66e9f36ea6e787fad54f0c413d52c226dc96fad36ccd33a0aa1930e
\ No newline at end of file
+d0278cdedfa04fb0b61838ab9622be8a2c462f58d5c3ebc4c5f802a727d0974e
\ No newline at end of file

diff --git a/src/expr.c b/src/expr.c
index a8e552f2c71b19bb4d864b2b951c7a4f366992bb..0c41f6684a5e9ce6a25c0c53d0a65b3b3397ca48 100644 (file)
--- a/src/expr.c
+++ b/src/expr.c
@@ -4690,8 +4690,7 @@ expr_code_doover:
           }
         }
 
-        sqlite3ExprCodeExprList(pParse, pFarg, r1, 0,
-                                SQLITE_ECEL_DUP|SQLITE_ECEL_FACTOR);
+        sqlite3ExprCodeExprList(pParse, pFarg, r1, 0, SQLITE_ECEL_FACTOR);
       }else{
         r1 = 0;
       }

diff --git a/src/json.c b/src/json.c
index 176dcbfdb9a56e75b5ea96aab0f489aa66113a6b..a9425aecda757fe7669f765e8068f969f43067b4 100644 (file)
--- a/src/json.c
+++ b/src/json.c
@@ -501,7 +501,8 @@ static void jsonAppendValue(
 */
 static void jsonResult(JsonString *p){
   if( p->bErr==0 ){
-    sqlite3_result_text64(p->pCtx, p->zBuf, p->nUsed, 
+    if( p->nAlloc>=p->nUsed+1 ) p->zBuf[p->nUsed] = 0;
+    sqlite3_result_text64(p->pCtx, p->zBuf, p->nUsed,
                           p->bStatic ? SQLITE_TRANSIENT : sqlite3_free,
                           SQLITE_UTF8);
     jsonZero(p);

diff --git a/src/vdbe.c b/src/vdbe.c
index b248a664d3c955c6ece7947dcaa4718dee66706b..075a6321177359a110c802ec9d5558c93b96f193 100644 (file)
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -556,6 +556,9 @@ void sqlite3VdbeMemPrettyPrint(Mem *pMem, StrAccum *pStr){
       sqlite3_str_appendchar(pStr, 1, (c>=0x20&&c<=0x7f) ? c : '.');
     }
     sqlite3_str_appendf(pStr, "]%s", encnames[pMem->enc]);
+    if( f & MEM_Term ){
+      sqlite3_str_appendf(pStr, "(0-term)");
+    }
   }
 }
 #endif
@@ -3085,6 +3088,9 @@ op_column_restart:
       rc = sqlite3VdbeMemFromBtree(pC->uc.pCursor, aOffset[p2], len, pDest);
       if( rc!=SQLITE_OK ) goto abort_due_to_error;
       sqlite3VdbeSerialGet((const u8*)pDest->z, t, pDest);
+      if( (t&1)!=0 && encoding==SQLITE_UTF8 ){
+        pDest->flags |= MEM_Term;
+      }
       pDest->flags &= ~MEM_Ephem;
     }
   }

diff --git a/src/vdbeapi.c b/src/vdbeapi.c
index 920780a896563f1d68fef3c14a20d75532e6ced2..7f44d22bc7352b3fcd47b2f89cbe225de40f3555 100644 (file)
--- a/src/vdbeapi.c
+++ b/src/vdbeapi.c
@@ -514,6 +514,15 @@ void sqlite3_result_text64(
     (void)invokeValueDestructor(z, xDel, pCtx);
   }else{
     setResultStrOrError(pCtx, z, (int)n, enc, xDel);
+    if( xDel==sqlite3_free && enc==SQLITE_UTF8 ){
+      Mem *pOut = pCtx->pOut;
+      if( pOut->z==z 
+       && sqlite3_msize(pOut->z)>=pOut->n+1
+       && pOut->z[n]==0
+      ){
+        pOut->flags |= MEM_Term;
+      }
+    }
   }
 }
 #ifndef SQLITE_OMIT_UTF16