-C Enhance\sautoincrement\sso\sthat\sit\sworks\swith\striggers\sthat\salso\sdo\r\nautoincrement\sinserts,\seven\smultiple\sinserts\sinto\sthe\ssame\stable.\r\nTicket\s#3928\s(CVS\s6807)
-D 2009-06-23T20:28:54
+C Simplify\sthings\sby\srolling\sthe\sfunctionality\sof\sbalance_shallower()\sinto\sbalance_nonroot().\s(CVS\s6808)
+D 2009-06-24T05:40:34
F Makefile.arm-wince-mingw32ce-gcc fcd5e9cd67fe88836360bb4f9ef4cb7f8e2fb5a0
F Makefile.in 8b8fb7823264331210cddf103831816c286ba446
F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
F src/backup.c ff50af53184a5fd7bdee4d620b5dabef74717c79
F src/bitvec.c 0ef0651714728055d43de7a4cdd95e703fac0119
F src/btmutex.c 9b899c0d8df3bd68f527b0afe03088321b696d3c
-F src/btree.c 807e32c181e681ffd3468d114b5cb11c63984842
+F src/btree.c 699c333dd98db2498eb17ca43b2a5482c9dd098f
F src/btree.h f70b694e8c163227369a66863b01fbff9009f323
-F src/btreeInt.h 7267e965e34314aa2bddbdde268b31e1034eda9c
+F src/btreeInt.h 55346bc14b939ad41b297942e8b1b581e960fb99
F src/build.c d930b3899aea564f01a581e0e9429d92fb5f98f0
F src/callback.c cb68b21b0d4ae7d11ae0e487933bce3323784dcf
F src/complete.c 5ad5c6cd4548211867c204c41a126d73a9fbcea0
F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
F tool/vdbe-compress.tcl 672f81d693a03f80f5ae60bfefacd8a349e76746
-P c5dc80e6bdd18a5ada728c8d5c9403ac233f1c9a
-R 8916621e1801546a3d0feafac918adbe
-U drh
-Z cb8dc29a045e11a78c5fa19e64b5f95b
+P 1330993de8eae7baeec24100216158063c9bdc19
+R a93d21d5217aa847ca2406219efba4db
+U danielk1977
+Z ce9bb99781cb9e1be1b1a4518af4f1e5
** May you share freely, never taking more than you give.
**
*************************************************************************
-** $Id: btree.c,v 1.641 2009/06/23 16:40:18 danielk1977 Exp $
+** $Id: btree.c,v 1.642 2009/06/24 05:40:34 danielk1977 Exp $
**
** This file implements a external (disk-based) database using BTrees.
** See the header comment on "btreeInt.h" for additional information.
return rc;
}
-/*
-** This routine is called on the root page of a btree when the root
-** page contains no cells. This is an opportunity to make the tree
-** shallower by one level.
-*/
-static int balance_shallower(MemPage *pRoot, MemPage *pChild){
- /* The root page is empty but has one child. Transfer the
- ** information from that one child into the root page if it
- ** will fit. This reduces the depth of the tree by one.
- **
- ** If the root page is page 1, it has less space available than
- ** its child (due to the 100 byte header that occurs at the beginning
- ** of the database fle), so it might not be able to hold all of the
- ** information currently contained in the child. If this is the
- ** case, then do not do the transfer. Leave page 1 empty except
- ** for the right-pointer to the child page. The child page becomes
- ** the virtual root of the tree.
- */
- int rc = SQLITE_OK; /* Return code */
- int const hdr = pRoot->hdrOffset; /* Offset of root page header */
-
- assert( sqlite3_mutex_held(pRoot->pBt->mutex) );
- assert( pRoot->nCell==0 );
- assert( pChild->pgno==get4byte(&pRoot->aData[pRoot->hdrOffset+8]) );
- assert( hdr==0 || pRoot->pgno==1 );
-
- if( pChild->nFree>=hdr ){
- if( hdr ){
- rc = defragmentPage(pChild);
- }
- if( rc==SQLITE_OK ){
- rc = copyNodeContent(pChild, pRoot);
- }
- if( rc==SQLITE_OK ){
- rc = freePage(pChild);
- }
- }
-
- return rc;
-}
-
/*
** This routine redistributes cells on the iParentIdx'th child of pParent
** (hereafter "the page") and up to 2 siblings so that all pages have about the
memcpy(&apNew[nNew-1]->aData[8], zChild, 4);
}
- /* Fix the pointer-map entries for all the cells that were shifted around.
- ** There are several different types of pointer-map entries that need to
- ** be dealt with by this routine. Some of these have been set already, but
- ** many have not. The following is a summary:
- **
- ** 1) The entries associated with new sibling pages that were not
- ** siblings when this function was called. These have already
- ** been set. We don't need to worry about old siblings that were
- ** moved to the free-list - the freePage() code has taken care
- ** of those.
- **
- ** 2) The pointer-map entries associated with the first overflow
- ** page in any overflow chains used by new divider cells. These
- ** have also already been taken care of by the insertCell() code.
- **
- ** 3) If the sibling pages are not leaves, then the child pages of
- ** cells stored on the sibling pages may need to be updated.
- **
- ** 4) If the sibling pages are not internal intkey nodes, then any
- ** overflow pages used by these cells may need to be updated
- ** (internal intkey nodes never contain pointers to overflow pages).
- **
- ** 5) If the sibling pages are not leaves, then the pointer-map
- ** entries for the right-child pages of each sibling may need
- ** to be updated.
- **
- ** Cases 1 and 2 are dealt with above by other code. The following
- ** block deals with cases 3 and 4. Since setting a pointer map entry
- ** is a relatively expensive operation, this code only sets pointer
- ** map entries for child or overflow pages that have actually moved
- ** between pages. */
- if( ISAUTOVACUUM ){
+ if( isRoot && pParent->nCell==0 && pParent->hdrOffset<=apNew[0]->nFree ){
+ /* The root page of the b-tree now contains no cells. The only sibling
+ ** page is the right-child of the parent. Copy the contents of the
+ ** child page into the parent, decreasing the overall height of the
+ ** b-tree structure by one. This is described as the "balance-shallower"
+ ** sub-algorithm in some documentation.
+ **
+ ** If this is an auto-vacuum database, the call to copyNodeContent()
+ ** sets all pointer-map entries corresponding to database image pages
+ ** for which the pointer is stored within the content being copied.
+ **
+ ** The second assert below verifies that the child page is defragmented
+ ** (it must be, as it was just reconstructed using assemblePage()). This
+ ** is important if the parent page happens to be page 1 of the database
+ ** image. */
+ assert( nNew==1 );
+ assert( apNew[0]->nFree ==
+ (get2byte(&apNew[0]->aData[5])-apNew[0]->cellOffset-apNew[0]->nCell*2)
+ );
+ if( SQLITE_OK==(rc = copyNodeContent(apNew[0], pParent)) ){
+ rc = freePage(apNew[0]);
+ }
+ }else if( ISAUTOVACUUM ){
+ /* Fix the pointer-map entries for all the cells that were shifted around.
+ ** There are several different types of pointer-map entries that need to
+ ** be dealt with by this routine. Some of these have been set already, but
+ ** many have not. The following is a summary:
+ **
+ ** 1) The entries associated with new sibling pages that were not
+ ** siblings when this function was called. These have already
+ ** been set. We don't need to worry about old siblings that were
+ ** moved to the free-list - the freePage() code has taken care
+ ** of those.
+ **
+ ** 2) The pointer-map entries associated with the first overflow
+ ** page in any overflow chains used by new divider cells. These
+ ** have also already been taken care of by the insertCell() code.
+ **
+ ** 3) If the sibling pages are not leaves, then the child pages of
+ ** cells stored on the sibling pages may need to be updated.
+ **
+ ** 4) If the sibling pages are not internal intkey nodes, then any
+ ** overflow pages used by these cells may need to be updated
+ ** (internal intkey nodes never contain pointers to overflow pages).
+ **
+ ** 5) If the sibling pages are not leaves, then the pointer-map
+ ** entries for the right-child pages of each sibling may need
+ ** to be updated.
+ **
+ ** Cases 1 and 2 are dealt with above by other code. The next
+ ** block deals with cases 3 and 4 and the one after that, case 5. Since
+ ** setting a pointer map entry is a relatively expensive operation, this
+ ** code only sets pointer map entries for child or overflow pages that have
+ ** actually moved between pages. */
MemPage *pNew = apNew[0];
MemPage *pOld = apCopy[0];
int nOverflow = pOld->nOverflow;
TRACE(("BALANCE: finished: old=%d new=%d cells=%d\n",
nOld, nNew, nCell));
- if( rc==SQLITE_OK && pParent->nCell==0 && isRoot ){
- /* The root page of the b-tree now contains no cells. If the root-page
- ** is not also a leaf page, it will have a single child page. Call
- ** balance_shallower to attempt to copy the contents of the single
- ** child-page into the root page (this may not be possible if the
- ** root page is page 1). */
- assert( nNew==1 );
- rc = balance_shallower(pParent, apNew[0]);
- }
-
/*
** Cleanup before returning.
*/
** balance_quick()
** balance_deeper()
** balance_nonroot()
-**
-** If built with SQLITE_DEBUG, pCur->pagesShuffled is set to true if
-** balance_shallower(), balance_deeper() or balance_nonroot() is called.
-** If none of these functions are invoked, pCur->pagesShuffled is left
-** unmodified.
*/
static int balance(BtCursor *pCur){
int rc = SQLITE_OK;
pCur->aiIdx[1] = 0;
assert( pCur->apPage[1]->nOverflow );
}
- VVA_ONLY( pCur->pagesShuffled = 1 );
}else{
break;
}
** balance_nonroot(), or just before this function returns, whichever
** comes first. */
pFree = pSpace;
- VVA_ONLY( pCur->pagesShuffled = 1 );
}
}
projects / thirdparty / sqlite.git / commitdiff
