Add the "PRAGMA reset_database=ON|OFF" command. When on, it causes the

database to appear to be empty, causing the next transaction to reset it to
an empty database.

FossilOrigin-Name: 02e1a13c1f04bb72599b98f51240c78d0d050de264fef5808fd97db3f4c16dac

diff --git a/manifest b/manifest
index df2c9b0e226226c3df55898af84520cb51a66f70..6a573c3c657f46ed44c9bfbc7354d085ae970b97 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Update\stest\sscript\sfts3expr4.test\sso\sthat\sit\salways\screates\sfts3\stokenizers\sin\nthe\s"en_US"\slocality.
-D 2018-04-27T18:05:01.487
+C Add\sthe\s"PRAGMA\sreset_database=ON|OFF"\scommand.\s\sWhen\son,\sit\scauses\sthe\ndatabase\sto\sappear\sto\sbe\sempty,\scausing\sthe\snext\stransaction\sto\sreset\sit\sto\nan\sempty\sdatabase.
+D 2018-04-28T01:27:09.774
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F Makefile.in 5ce9343cba9c189046f1afe6d2bcc1f68079439febc05267b98aec6ecc752439
@@ -433,7 +433,7 @@ F src/auth.c 6277d63837357549fe14e723490d6dc1a38768d71c795c5eb5c0f8a99f918f73
 F src/backup.c faf17e60b43233c214aae6a8179d24503a61e83b
 F src/bitvec.c 17ea48eff8ba979f1f5b04cc484c7bb2be632f33
 F src/btmutex.c 8acc2f464ee76324bf13310df5692a262b801808984c1b79defb2503bbafadb6
-F src/btree.c 9eb9531c65346bbfccf5325384b7db1849daf4db6601dcfe21ba5c5b20623b64
+F src/btree.c fa7da0a5584e5182b92536bc4b7622a154a468997a075d5901345efb79a05ffe
 F src/btree.h 0866c0a08255142ea0e754aabd211c843cab32045c978a592a43152405ed0c84
 F src/btreeInt.h 620ab4c7235f43572cf3ac2ac8723cbdf68073be4d29da24897c7b77dda5fd96
 F src/build.c c4227d058d52c24ffce2d33cd3a11234d8e8603901243cdb5165eddf64ee2177
@@ -486,8 +486,8 @@ F src/pcache.c 135ef0bc6fb2e3b7178d49ab5c9176254c8a691832c1bceb1156b2fbdd0869bd
 F src/pcache.h 072f94d29281cffd99e46c1539849f248c4b56ae7684c1f36626797fee375170
 F src/pcache1.c 716975564c15eb6679e97f734cec1bfd6c16ac3d4010f05f1f8e509fc7d19880
 F src/pragma.c bea56df3ae0637768c0da4fbbb8f2492f780980d95000034a105ff291bf7ca69
-F src/pragma.h bb83728944b42f6d409c77f5838a8edbdb0fe83046c5496ffc9602b40340a324
-F src/prepare.c d16cb8a553c09bc0c46c33f8e0add77c8f755cfb4681ca5101aaff3a04df9625
+F src/pragma.h f1e9f51dcd93188cd0b2eb8a616eaf3e79e17c3279f68aec8d0bd49546dcb909
+F src/prepare.c 1492a2bed7bc5770c5850404f09bf887a67d4580985b8cee37bdab2ea809f479
 F src/printf.c d3b7844ddeb11fbbdd38dd84d09c9c1ac171d21fb038473c3aa97981201cc660
 F src/random.c 80f5d666f23feb3e6665a6ce04c7197212a88384
 F src/resolve.c 6415381a0e9d22c0e7cba33ca4a53f81474190862f5d4838190f5eb5b0b47bc9
@@ -497,7 +497,7 @@ F src/shell.c.in d63f06c870ec1761ea98bd1cae651ff0ea6beadf8be892105dabd913f94cb3d
 F src/sqlite.h.in 8e70752a57597c08f64f3d49fc1fc46926b862d2e23b038b0d23b9cc748d88ea
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h 83a3c4ce93d650bedfd1aa558cb85a516bd6d094445ee989740827d0d944368d
-F src/sqliteInt.h c1deb023eb117b4437a69d8c5a753deb36581f1933015cd262ad32b45c4d8431
+F src/sqliteInt.h 8ac0138eae10337b745b03dad0124fd63ae911c0503e795729503e7fc6234d57
 F src/sqliteLimit.h 1513bfb7b20378aa0041e7022d04acb73525de35b80b252f1b83fedb4de6a76b
 F src/status.c 46e7aec11f79dad50965a5ca5fa9de009f7d6bde08be2156f1538a0a296d4d0e
 F src/table.c b46ad567748f24a326d9de40e5b9659f96ffff34
@@ -1658,7 +1658,7 @@ F tool/mkmsvcmin.tcl cad0c7b54d7dd92bc87d59f36d4cc4f070eb2e625f14159dc2f5c4204e6
 F tool/mkopcodec.tcl d1b6362bd3aa80d5520d4d6f3765badf01f6c43c
 F tool/mkopcodeh.tcl 4ee2a30ccbd900dc4d5cdb61bdab87cd2166cd2affcc78c9cc0b8d22a65b2eee
 F tool/mkopts.tcl 680f785fdb09729fd9ac50632413da4eadbdf9071535e3f26d03795828ab07fa
-F tool/mkpragmatab.tcl 2144bc8550a6471a029db262a132d2df4b9e0db61b90398bf64f5b7b3f8d92cd
+F tool/mkpragmatab.tcl c2efde2e98beee55f04679cac652a1a6291b6e47e3b0c5b86f53b84c174d9b5e
 F tool/mkshellc.tcl 1f45770aea226ac093a9c72f718efbb88a2a2833409ec2e1c4cecae4202626f5
 F tool/mksourceid.c d458f9004c837bee87a6382228ac20d3eae3c49ea3b0a5aace936f8b60748d3b
 F tool/mkspeedsql.tcl a1a334d288f7adfe6e996f2e712becf076745c97
@@ -1725,7 +1725,10 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 462b52b121c1882e0eca819bc30c0f6e94d7fdd60047d2c32adeff3a1eb70546
-R 330eca5f95eacfc2db564f6137a9dfe2
-U dan
-Z a32eb6502eb10fd4922091ca79205291
+P 576a8f69ae25883f752e58953624e9f7126db998bebaa1f07f7c2ec47aaecabe
+R 20267b33ec4093cbd8eada610413a5f9
+T *branch * reset-database
+T *sym-reset-database *
+T -sym-trunk *
+U drh
+Z 6b0d829800a54a9640942b2a1f1f52ea

diff --git a/manifest.uuid b/manifest.uuid
index 4ebdf5064e24b29d71495a22608126b9059de42d..429266b2c5ff59424243d5f075803c34d2d59216 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-576a8f69ae25883f752e58953624e9f7126db998bebaa1f07f7c2ec47aaecabe
\ No newline at end of file
+02e1a13c1f04bb72599b98f51240c78d0d050de264fef5808fd97db3f4c16dac
\ No newline at end of file

diff --git a/src/btree.c b/src/btree.c
index 402503916df6a04251909af34e2873004f747160..700138efca82329cbde5158755e3859e70fdd298 100644 (file)
--- a/src/btree.c
+++ b/src/btree.c
@@ -2972,6 +2972,10 @@ static void setDefaultSyncFlag(BtShared *pBt, u8 safety_level){
 # define setDefaultSyncFlag(pBt,safety_level)
 #endif
 
+/* Forward declaration */
+static int newDatabase(BtShared*);
+
+
 /*
 ** Get a reference to pPage1 of the database file.  This will
 ** also acquire a readlock on that file.
@@ -3003,6 +3007,9 @@ static int lockBtree(BtShared *pBt){
   if( nPage==0 || memcmp(24+(u8*)pPage1->aData, 92+(u8*)pPage1->aData,4)!=0 ){
     nPage = nPageFile;
   }
+  if( (pBt->db->flags & SQLITE_ResetDatabase)!=0 ){
+    nPage = 0;
+  }
   if( nPage>0 ){
     u32 pageSize;
     u32 usableSize;

diff --git a/src/pragma.h b/src/pragma.h
index c9ece2dc875f8232c6c30a8b788c1dbc0507f7dd..a1695ff98bd5c490c6f1153e457ea87c7d94a05d 100644 (file)
--- a/src/pragma.h
+++ b/src/pragma.h
@@ -506,6 +506,11 @@ static const PragmaName aPragmaName[] = {
   /* iArg:      */ 0 },
 #endif
 #if !defined(SQLITE_OMIT_FLAG_PRAGMAS)
+ {/* zName:     */ "reset_database",
+  /* ePragTyp:  */ PragTyp_FLAG,
+  /* ePragFlg:  */ PragFlg_Result0|PragFlg_NoColumns1,
+  /* ColNames:  */ 0, 0,
+  /* iArg:      */ SQLITE_WriteSchema|SQLITE_ResetDatabase },
  {/* zName:     */ "reverse_unordered_selects",
   /* ePragTyp:  */ PragTyp_FLAG,
   /* ePragFlg:  */ PragFlg_Result0|PragFlg_NoColumns1,
@@ -646,4 +651,4 @@ static const PragmaName aPragmaName[] = {
   /* iArg:      */ SQLITE_WriteSchema },
 #endif
 };
-/* Number of pragmas: 60 on by default, 77 total. */
+/* Number of pragmas: 61 on by default, 78 total. */

diff --git a/src/prepare.c b/src/prepare.c
index c13f88d28bc290fac5851160a1fb0b25932fedea..971b8024e8beab0a6540e62205a27f48af17fb21 100644 (file)
--- a/src/prepare.c
+++ b/src/prepare.c
@@ -216,6 +216,9 @@ static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
   for(i=0; i<ArraySize(meta); i++){
     sqlite3BtreeGetMeta(pDb->pBt, i+1, (u32 *)&meta[i]);
   }
+  if( (db->flags & SQLITE_ResetDatabase)!=0 ){
+    memset(meta, 0, sizeof(meta));
+  }
   pDb->pSchema->schema_cookie = meta[BTREE_SCHEMA_VERSION-1];
 
   /* If opening a non-empty database, check the text encoding. For the

diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 8ad15109a8ef16cc4b11954449a7ea07488741b2..c700c261b8c142a6d2cc4c1fbe8f5ab80224c874 100644 (file)
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -1506,6 +1506,7 @@ struct sqlite3 {
 #define SQLITE_Fts3Tokenizer  0x00400000  /* Enable fts3_tokenizer(2) */
 #define SQLITE_EnableQPSG     0x00800000  /* Query Planner Stability Guarantee*/
 #define SQLITE_TriggerEQP     0x01000000  /* Show trigger EXPLAIN QUERY PLAN */
+#define SQLITE_ResetDatabase  0x02000000  /* Reset the database */
 
 /* Flags used only if debugging */
 #ifdef SQLITE_DEBUG

diff --git a/tool/mkpragmatab.tcl b/tool/mkpragmatab.tcl
index 1bfbeb7c58befc4e916a48e60f2e18b55d594bf2..690edaff239f1dae7c367a62f3e77535e39406a2 100644 (file)
--- a/tool/mkpragmatab.tcl
+++ b/tool/mkpragmatab.tcl
@@ -123,6 +123,11 @@ set pragma_def {
   ARG:  SQLITE_WriteSchema
   IF:   !defined(SQLITE_OMIT_FLAG_PRAGMAS)
 
+  NAME: reset_database
+  TYPE: FLAG
+  ARG:  SQLITE_WriteSchema|SQLITE_ResetDatabase
+  IF:   !defined(SQLITE_OMIT_FLAG_PRAGMAS)
+
   NAME: read_uncommitted
   TYPE: FLAG
   ARG:  SQLITE_ReadUncommit