Improve the performance of the .recover command.

FossilOrigin-Name: a50768314d10d743a0cc013b434b516f0763e0a6c5b79655d8fefde7de53e869

diff --git a/ext/misc/dbdata.c b/ext/misc/dbdata.c
index 7662417ae550a169cbd519b3e4523c0eec097d94..13bb51f08bf01944c0052e73363086c6bf34ceb1 100644 (file)
--- a/ext/misc/dbdata.c
+++ b/ext/misc/dbdata.c
@@ -106,6 +106,7 @@ struct DbdataCursor {
 struct DbdataTable {
   sqlite3_vtab base;              /* Base class.  Must be first */
   sqlite3 *db;                    /* The database connection */
+  sqlite3_stmt *pStmt;            /* For fetching database pages */
   int bPtr;                       /* True for sqlite3_dbptr table */
 };
 
@@ -167,7 +168,11 @@ static int dbdataConnect(
 ** Disconnect from or destroy a dbdata virtual table.
 */
 static int dbdataDisconnect(sqlite3_vtab *pVtab){
-  sqlite3_free(pVtab);
+  DbdataTable *pTab = (DbdataTable*)pVtab;
+  if( pTab ){
+    sqlite3_finalize(pTab->pStmt);
+    sqlite3_free(pVtab);
+  }
   return SQLITE_OK;
 }
 
@@ -185,15 +190,15 @@ static int dbdataDisconnect(sqlite3_vtab *pVtab){
 ** If both parameters are present, schema is in position 0 and pgno in
 ** position 1.
 */
-static int dbdataBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
+static int dbdataBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdx){
   DbdataTable *pTab = (DbdataTable*)tab;
   int i;
   int iSchema = -1;
   int iPgno = -1;
   int colSchema = (pTab->bPtr ? DBPTR_COLUMN_SCHEMA : DBDATA_COLUMN_SCHEMA);
 
-  for(i=0; i<pIdxInfo->nConstraint; i++){
-    struct sqlite3_index_constraint *p = &pIdxInfo->aConstraint[i];
+  for(i=0; i<pIdx->nConstraint; i++){
+    struct sqlite3_index_constraint *p = &pIdx->aConstraint[i];
     if( p->op==SQLITE_INDEX_CONSTRAINT_EQ ){
       if( p->iColumn==colSchema ){
         if( p->usable==0 ) return SQLITE_CONSTRAINT;
@@ -206,14 +211,29 @@ static int dbdataBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
   }
 
   if( iSchema>=0 ){
-    pIdxInfo->aConstraintUsage[iSchema].argvIndex = 1;
-    pIdxInfo->aConstraintUsage[iSchema].omit = 1;
+    pIdx->aConstraintUsage[iSchema].argvIndex = 1;
+    pIdx->aConstraintUsage[iSchema].omit = 1;
   }
   if( iPgno>=0 ){
-    pIdxInfo->aConstraintUsage[iPgno].argvIndex = 1 + (iSchema>=0);
-    pIdxInfo->aConstraintUsage[iPgno].omit = 1;
+    pIdx->aConstraintUsage[iPgno].argvIndex = 1 + (iSchema>=0);
+    pIdx->aConstraintUsage[iPgno].omit = 1;
+    pIdx->estimatedCost = 100;
+    pIdx->estimatedRows =  50;
+
+    if( pTab->bPtr==0 && pIdx->nOrderBy && pIdx->aOrderBy[0].desc==0 ){
+      int iCol = pIdx->aOrderBy[0].iColumn;
+      if( pIdx->nOrderBy==1 ){
+        pIdx->orderByConsumed = (iCol==0 || iCol==1);
+      }else if( pIdx->nOrderBy==2 && pIdx->aOrderBy[1].desc==0 && iCol==0 ){
+        pIdx->orderByConsumed = (pIdx->aOrderBy[1].iColumn==1);
+      }
+    }
+
+  }else{
+    pIdx->estimatedCost = 100000000;
+    pIdx->estimatedRows = 1000000000;
   }
-  pIdxInfo->idxNum = (iSchema>=0 ? 0x01 : 0x00) | (iPgno>=0 ? 0x02 : 0x00);
+  pIdx->idxNum = (iSchema>=0 ? 0x01 : 0x00) | (iPgno>=0 ? 0x02 : 0x00);
   return SQLITE_OK;
 }
 
@@ -236,7 +256,12 @@ static int dbdataOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
 }
 
 static void dbdataResetCursor(DbdataCursor *pCsr){
-  sqlite3_finalize(pCsr->pStmt);
+  DbdataTable *pTab = (DbdataTable*)(pCsr->base.pVtab);
+  if( pTab->pStmt==0 ){
+    pTab->pStmt = pCsr->pStmt;
+  }else{
+    sqlite3_finalize(pCsr->pStmt);
+  }
   pCsr->pStmt = 0;
   pCsr->iPgno = 1;
   pCsr->iCell = 0;
@@ -558,7 +583,7 @@ static int dbdataFilter(
 ){
   DbdataCursor *pCsr = (DbdataCursor*)pCursor;
   DbdataTable *pTab = (DbdataTable*)pCursor->pVtab;
-  int rc;
+  int rc = SQLITE_OK;
   const char *zSchema = "main";
 
   dbdataResetCursor(pCsr);
@@ -571,10 +596,15 @@ static int dbdataFilter(
     pCsr->bOnePage = 1;
   }
 
-  rc = sqlite3_prepare_v2(pTab->db, 
-      "SELECT data FROM sqlite_dbpage(?) WHERE pgno=?", -1,
-      &pCsr->pStmt, 0
-  );
+  if( pTab->pStmt ){
+    pCsr->pStmt = pTab->pStmt;
+    pTab->pStmt = 0;
+  }else{
+    rc = sqlite3_prepare_v2(pTab->db, 
+        "SELECT data FROM sqlite_dbpage(?) WHERE pgno=?", -1,
+        &pCsr->pStmt, 0
+    );
+  }
   if( rc==SQLITE_OK ){
     rc = sqlite3_bind_text(pCsr->pStmt, 1, zSchema, -1, SQLITE_TRANSIENT);
   }else{

diff --git a/manifest b/manifest
index e3ab13575f784bbe7bc2b7a7ac0741ecac17df98..039fa636853a7007c8840aa44a83d34f487f7ca9 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Have\s".recover"\shandle\s"\\r"\sand\s"\\n"\sin\sthe\ssame\sway\sas\s".dump".
-D 2019-04-23T20:48:32.366
+C Improve\sthe\sperformance\sof\sthe\s.recover\scommand.
+D 2019-04-24T20:48:55.802
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -284,7 +284,7 @@ F ext/misc/closure.c dbfd8543b2a017ae6b1a5843986b22ddf99ff126ec9634a2f4047cd14c8
 F ext/misc/completion.c cec672d40604075bb341a7f11ac48393efdcd90a979269b8fe7977ea62d0547f
 F ext/misc/compress.c dd4f8a6d0baccff3c694757db5b430f3bbd821d8686d1fc24df55cf9f035b189
 F ext/misc/csv.c 7f047aeb68f5802e7ce6639292095d622a488bb43526ed04810e0649faa71ceb
-F ext/misc/dbdata.c 6a0ccc33e8c5ef3b6164eec7839cb4dff44e27bee0717f1660dbb8ee77ee4cf8
+F ext/misc/dbdata.c 0c80f0757c3a1b5c57027328ab0ccfe30fcef1a4875b41dd9ddc0f53c7087e97
 F ext/misc/dbdump.c baf6e37447c9d6968417b1cd34cbedb0b0ab3f91b5329501d8a8d5be3287c336
 F ext/misc/eval.c 4b4757592d00fd32e44c7a067e6a0e4839c81a4d57abc4131ee7806d1be3104e
 F ext/misc/explain.c d5c12962d79913ef774b297006872af1fccda388f61a11d37758f9179a09551f
@@ -520,7 +520,7 @@ F src/random.c 80f5d666f23feb3e6665a6ce04c7197212a88384
 F src/resolve.c 567888ee3faec14dae06519b4306201771058364a37560186a3e0e755ebc4cb8
 F src/rowset.c d977b011993aaea002cab3e0bb2ce50cf346000dff94e944d547b989f4b1fe93
 F src/select.c 9263f5c30dd44c7ac2eb29f40a7ec64322a96885b71c00de6bc30b756c2e1c49
-F src/shell.c.in 6e56c60640410885a8c3c264971619407ae5c7f46165e2bfe5fb1ca1a6a58ad0
+F src/shell.c.in 569ee1f79236f19b44fb4fcb8a0a2f0b2dce9a3d856d41a196aaaaa5f0d37704
 F src/sqlite.h.in 38390767acc1914d58930e03149595ee4710afa4e3c43ab6c3a8aea3f1a6b8cd
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h 9ecc93b8493bd20c0c07d52e2ac0ed8bab9b549c7f7955b59869597b650dd8b5
@@ -1821,7 +1821,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 8dcc1d89d955bf58c80a8c30a37960f0cf95719953951a92626cc332cc75ec60
-R b9c18dd1095e3f7b028bdaea88f9fcb0
+P f95f0f02ab6c6cf45f25b613c7ab57f68249689d0a9eddf4c9518ddf0edad365
+R 0e7ee563b8599ed64c48e30038f5f99f
 U dan
-Z edabfc3afbc2656b0ce1a8fb6b1e492b
+Z f093e1d7a99537670d8620da5d0b299b

diff --git a/manifest.uuid b/manifest.uuid
index fdcc68f9a95e32e9c2b6e3e6ac5cbc33f50b6daf..3f613030655297302b7730b1097ab4ccd4608b34 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-f95f0f02ab6c6cf45f25b613c7ab57f68249689d0a9eddf4c9518ddf0edad365
\ No newline at end of file
+a50768314d10d743a0cc013b434b516f0763e0a6c5b79655d8fefde7de53e869
\ No newline at end of file

diff --git a/src/shell.c.in b/src/shell.c.in
index 7989c9dfdef0c060b786e0ac217611bd375cb800..05ce02d605d75f20e98c6be2cfb06c487441809b 100644 (file)
--- a/src/shell.c.in
+++ b/src/shell.c.in
@@ -6372,6 +6372,8 @@ static RecoverTable *recoverNewTable(
 static int recoverDatabaseCmd(ShellState *pState){
   int rc = SQLITE_OK;
   sqlite3_stmt *pLoop = 0;        /* Loop through all root pages */
+  sqlite3_stmt *pPages = 0;       /* Loop through all pages in a group */
+  sqlite3_stmt *pCells = 0;       /* Loop through all cells in a page */
 
   shellExec(pState->db, &rc, 
     /* Attach an in-memory database named 'recovery'. Create an indexed 
@@ -6460,6 +6462,15 @@ static int recoverDatabaseCmd(ShellState *pState){
     shellFinalize(&rc, pStmt);
   }
 
+  shellPrepare(pState->db, &rc,
+      "SELECT pgno FROM recovery.map WHERE root=?", &pPages
+  );
+  shellPrepare(pState->db, &rc,
+      "SELECT max(field), group_concat(shell_escape_crnl(quote(value)), ', ')"
+      "FROM sqlite_dbdata WHERE pgno = ? AND field != ?"
+      "GROUP BY cell", &pCells
+  );
+
   /* Loop through each root page. */
   shellPrepare(pState->db, &rc, 
       "SELECT root, intkey, max(maxlen) FROM recovery.map" 
@@ -6475,30 +6486,29 @@ static int recoverDatabaseCmd(ShellState *pState){
 
     pTab = recoverNewTable(pState, &rc, iRoot, bIntkey, nCol);
     if( pTab ){
-      sqlite3_stmt *pData = 0;
       if( 0==sqlite3_stricmp(pTab->zName, "sqlite_sequence") ){
         raw_printf(pState->out, "DELETE FROM sqlite_sequence;\n");
       }
-      shellPreparePrintf(pState->db, &rc, &pData, 
-        "SELECT max(field), group_concat(shell_escape_crnl(quote(value)),', ')"
-        "FROM sqlite_dbdata WHERE pgno IN ("
-        "  SELECT pgno FROM recovery.map WHERE root=%d"
-        ")"
-        " AND field!=%d "
-        "GROUP BY pgno, cell;", iRoot, pTab->iPk
-      );
-      while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pData) ){
-        int iMax = sqlite3_column_int(pData, 0);
-        const char *zVal = (const char*)sqlite3_column_text(pData, 1);
-        raw_printf(pState->out, "INSERT INTO %s(%s) VALUES( %s );\n", 
-            pTab->zQuoted, pTab->azlCol[iMax>0?iMax:0], zVal
-        );
+      sqlite3_bind_int(pPages, 1, iRoot);
+      sqlite3_bind_int(pCells, 2, pTab->iPk);
+      while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pPages) ){
+        sqlite3_bind_int(pCells, 1, sqlite3_column_int(pPages, 0));
+        while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pCells) ){
+          int iMax = sqlite3_column_int(pCells, 0);
+          const char *zVal = (const char*)sqlite3_column_text(pCells, 1);
+          raw_printf(pState->out, "INSERT INTO %s(%s) VALUES( %s );\n", 
+              pTab->zQuoted, pTab->azlCol[iMax>0?iMax:0], zVal
+          );
+        }
+        shellReset(&rc, pCells);
       }
-      shellFinalize(&rc, pData);
+      shellReset(&rc, pPages);
     }
     recoverFreeTable(pTab);
   }
   shellFinalize(&rc, pLoop);
+  shellFinalize(&rc, pPages);
+  shellFinalize(&rc, pCells);
 
   /* The rest of the schema */
   if( rc==SQLITE_OK ){