From: drh <>
Date: Tue, 20 Aug 2024 12:15:08 +0000 (+0000)
Subject: The LIKE/GLOB optimization restricts its attention to
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=200a01c467f7b3dafcf1af0fd2937130c4e56300;p=thirdparty%2Fsqlite.git

The LIKE/GLOB optimization restricts its attention to
the pattern prefix that is all ASCII.

FossilOrigin-Name: 5815f13263b58c5cd9833f18c7fd8e5463255814d4cba72a5ed427cbd8105f8c
---

diff --git a/manifest b/manifest
index 3101658c80..619a940621 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\sleap-year\shandling\sfor\sdates\sprior\sto\s0400-03-01.
-D 2024-08-19T14:23:57.073
+C The\sLIKE/GLOB\soptimization\srestricts\sits\sattention\sto\nthe\spattern\sprefix\sthat\sis\sall\sASCII.
+D 2024-08-20T12:15:08.795
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -842,7 +842,7 @@ F src/walker.c 7c7ea0115345851c3da4e04e2e239a29983b61fb5b038b94eede6aba462640e2
 F src/where.c 839956666ce9f6b5d4951fc1f27e976951aac66920c82f9cdc5036b61b54ef7b
 F src/whereInt.h 82a13766f13d1a53b05387c2e60726289ef26404bc7b9b1f7770204d97357fb8
 F src/wherecode.c f5255f49d1f42b6e7e6b0362ff3522fa88cbcaa7213e52f9374744027ecdebca
-F src/whereexpr.c 67d15caf88a1a9528283d68ff578e024cf9fe810b517bb0343e5aaf695ad97dd
+F src/whereexpr.c c9a7a316b90db8904721a3c7bef7ed7784c290b50e66b38d7ceb6b3d55b4369d
 F src/window.c 5d95122dd330bfaebd732358c8ef067c5a9394a53ac249470d611d0ce2c52be2
 F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
 F test/affinity2.test ce1aafc86e110685b324e9a763eab4f2a73f737842ec3b687bd965867de90627
@@ -2192,9 +2192,9 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P c9c2ab54ba1f5f46360f1b4f35d849cd3f080e6fc2b6c60e91b16c63f69a1e33
-Q +474b7e34b83bc5e85854bc3b386f31ff39b390549d89b94921f33bbc5b658d1d
-R 1e40592919c74a0f6624604d0cccc039
+P 6767bf1c6713795a360da218a4e0f8106a264b54333849dd18b951ef6a82cba4
+Q +a5797ebdea423afc3d2d3bd8adaf1575d33a01f594c0c315afcb1499f1718e9b
+R 6ae4235d229175ca41696bab784b34cf
 U drh
-Z e341397c58ff7c6668cbd648792386ce
+Z 43e922e062feb2d968832b46f3a6397c
 # Remove this line to create a well-formed Fossil manifest.
diff --git a/manifest.uuid b/manifest.uuid
index 2d58f211ab..41a6e77263 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-6767bf1c6713795a360da218a4e0f8106a264b54333849dd18b951ef6a82cba4
+5815f13263b58c5cd9833f18c7fd8e5463255814d4cba72a5ed427cbd8105f8c
diff --git a/src/whereexpr.c b/src/whereexpr.c
index 5465dc953b..992ac07264 100644
--- a/src/whereexpr.c
+++ b/src/whereexpr.c
@@ -214,11 +214,20 @@ static int isLikeOrGlob(
   }
   if( z ){
 
-    /* Count the number of prefix characters prior to the first wildcard */
+    /* Count the number of prefix characters prior to the first wildcard.
+    ** If the underlying database has a UTF16LE encoding, then only consider
+    ** ASCII characters.  Note that the encoding of z[] is UTF8 - we are
+    ** dealing with only UTF8 here in this code, but the database engine
+    ** itself might be processing content using a different encoding. */
     cnt = 0;
     while( (c=z[cnt])!=0 && c!=wc[0] && c!=wc[1] && c!=wc[2] ){
       cnt++;
-      if( c==wc[3] && z[cnt]!=0 ) cnt++;
+      if( c==wc[3] && z[cnt]!=0 ){
+        cnt++;
+      }else if( c>=0x80 && ENC(db)==SQLITE_UTF16LE ){
+         cnt--;
+         break;
+      }
     }
 
     /* The optimization is possible only if (1) the pattern does not begin