Chagnes the ESCAPE clause on the LIKE operator to overwrite wildcard

characters, in order ot match the behavior of PosgreSQL.

FossilOrigin-Name: 11e0844f71e8f2d27ce9363fb505e02fd7795c61dae0b3886cf0d8df4484dd97

1 files changed, 19 insertions, 8 deletions

diff --git a/src/func.c b/src/func.c
index 966a0075e..167b6afd7 100644
--- a/src/func.c
+++ b/src/func.c
@@ -853,6 +853,7 @@ static void likeFunc(
   int nPat;
   sqlite3 *db = sqlite3_context_db_handle(context);
   struct compareInfo *pInfo = sqlite3_user_data(context);
+  struct compareInfo backupInfo;
 
 #ifdef SQLITE_LIKE_DOESNT_MATCH_BLOBS
   if( sqlite3_value_type(argv[0])==SQLITE_BLOB
@@ -888,6 +889,12 @@ static void likeFunc(
       return;
     }
     escape = sqlite3Utf8Read(&zEsc);
+    if( escape==pInfo->matchAll || escape==pInfo->matchOne ){
+      memcpy(&backupInfo, pInfo, sizeof(backupInfo));
+      pInfo = &backupInfo;
+      if( escape==pInfo->matchAll ) pInfo->matchAll = 0;
+      if( escape==pInfo->matchOne ) pInfo->matchOne = 0;
+    }
   }else{
     escape = pInfo->matchSet;
   }
@@ -1870,6 +1877,16 @@ int sqlite3IsLikeFunction(sqlite3 *db, Expr *pExpr, int *pIsNocase, char *aWc){
   if( NEVER(pDef==0) || (pDef->funcFlags & SQLITE_FUNC_LIKE)==0 ){
     return 0;
   }
+
+  /* The memcpy() statement assumes that the wildcard characters are
+  ** the first three statements in the compareInfo structure.  The
+  ** asserts() that follow verify that assumption
+  */
+  memcpy(aWc, pDef->pUserData, 3);
+  assert( (char*)&likeInfoAlt == (char*)&likeInfoAlt.matchAll );
+  assert( &((char*)&likeInfoAlt)[1] == (char*)&likeInfoAlt.matchOne );
+  assert( &((char*)&likeInfoAlt)[2] == (char*)&likeInfoAlt.matchSet );
+
   if( nExpr<3 ){
     aWc[3] = 0;
   }else{
@@ -1878,17 +1895,11 @@ int sqlite3IsLikeFunction(sqlite3 *db, Expr *pExpr, int *pIsNocase, char *aWc){
     if( pEscape->op!=TK_STRING ) return 0;
     zEscape = pEscape->u.zToken;
     if( zEscape[0]==0 || zEscape[1]!=0 ) return 0;
+    if( zEscape[0]==aWc[0] ) return 0;
+    if( zEscape[0]==aWc[1] ) return 0;
     aWc[3] = zEscape[0];
   }
 
-  /* The memcpy() statement assumes that the wildcard characters are
-  ** the first three statements in the compareInfo structure.  The
-  ** asserts() that follow verify that assumption
-  */
-  memcpy(aWc, pDef->pUserData, 3);
-  assert( (char*)&likeInfoAlt == (char*)&likeInfoAlt.matchAll );
-  assert( &((char*)&likeInfoAlt)[1] == (char*)&likeInfoAlt.matchOne );
-  assert( &((char*)&likeInfoAlt)[2] == (char*)&likeInfoAlt.matchSet );
   *pIsNocase = (pDef->funcFlags & SQLITE_FUNC_CASE)==0;
   return 1;
 }