database/sqlite
1
0
Fork 0
mirror of https://github.com/sqlite/sqlite.git synced 2025-08-07 02:42:48 +03:00
Code Activity

Add the ability to enable or disable SQLITE_IOCAP_ZERO_DAMAGE using a URI

Browse Source 
parameter for both unix and windows.  Add a file-control to query or disable
the ZERO_DAMAGE setting.  Add the -uri option to the "sqlite3" TCL command
in tclsqlite3.c.  Allow the sqlite3_uri_parameter() interface to accept a
NULL pointer for its first parameter.

FossilOrigin-Name: c83627b73285f883719845c1b9fe85f378f28dd2
This commit is contained in:
drh
2011-12-21 14:42:29 +00:00
parent f694aa6454
commit f12b3f609f
9 changed files with 254 additions and 41 deletions
Download Patch File Download Diff File Expand all files Collapse all files

23
manifest
View File

@@ -1,5 +1,5 @@
C Remove\sthe\scode\sthat\stries\sto\sdetect\sOOO\sheader\swrites\son\sa\sWAL\srecovery.\nThe\scode\sis\smade\sobsolete\sby\ssyncing\sthe\sWAL\sheader.
D 2011-12-20T22:18:51.258
C Add\sthe\sability\sto\senable\sor\sdisable\sSQLITE_IOCAP_ZERO_DAMAGE\susing\sa\sURI\nparameter\sfor\sboth\sunix\sand\swindows.\s\sAdd\sa\sfile-control\sto\squery\sor\sdisable\nthe\sZERO_DAMAGE\ssetting.\s\sAdd\sthe\s-uri\soption\sto\sthe\s"sqlite3"\sTCL\scommand\nin\stclsqlite3.c.\s\sAllow\sthe\ssqlite3_uri_parameter()\sinterface\sto\saccept\sa\nNULL\spointer\sfor\sits\sfirst\sparameter.
D 2011-12-21T14:42:29.520
F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
F Makefile.in 5b4a3e12a850b021547e43daf886b25133b44c07
F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -147,7 +147,7 @@ F src/journal.c 552839e54d1bf76fb8f7abe51868b66acacf6a0e
F src/legacy.c a199d7683d60cef73089e892409113e69c23a99f
F src/lempar.c 0ee69fca0be54cd93939df98d2aca4ca46f44416
F src/loadext.c f20382fbaeec832438a1ba7797bee3d3c8a6d51d
F src/main.c c837e24182e8ec7121c61e44f547b59cbe413e7f
F src/main.c 7f960366043b80c764de07e745d12b0705f56b30
F src/malloc.c 591aedb20ae40813f1045f2ef253438a334775d9
F src/mem0.c 6a55ebe57c46ca1a7d98da93aaa07f99f1059645
F src/mem1.c 7998e7003a3047e323c849a26dda004debc04d03
@@ -166,8 +166,8 @@ F src/os.c 28bbdab2170dfce84d86c45456a18eab1d0f99a9
F src/os.h 549b1a2e5e0ed1e1499f252dac126c4973e7379c
F src/os_common.h 92815ed65f805560b66166e3583470ff94478f04
F src/os_os2.c 4a75888ba3dfc820ad5e8177025972d74d7f2440
F src/os_unix.c e2b96f85eb91c962765005892014b014db3e6478
F src/os_win.c 3cf34661f5ef47be81bb7be541582d6e14852159
F src/os_unix.c 3e630701efd54ecbdba237c5a3cb3c55d83d8a2e
F src/os_win.c 4fc4aa8aecb334c64a250a4b36cff6a798704da4
F src/pager.c c9bd2f7183edba480bea1dd49361a02d0c3d8f43
F src/pager.h 5cd760857707529b403837d813d86b68938d6183
F src/parse.y fabb2e7047417d840e6fdb3ef0988a86849a08ba
@@ -182,14 +182,14 @@ F src/resolve.c 3d3e80a98f203ac6b9329e9621e29eda85ddfd40
F src/rowset.c 69afa95a97c524ba6faf3805e717b5b7ae85a697
F src/select.c a1d075db66a0ea42807353501b62997969e5be79
F src/shell.c aa4183d4a5243d8110b1d3d77faa4aea7e9c9c2d
F src/sqlite.h.in d0e81fd4c72fbfdc786d3067e17a16a32f249428
F src/sqlite.h.in 369e7597b7673e8bc490e2012bc00fb15cd55674
F src/sqlite3ext.h 6904f4aadf976f95241311fbffb00823075d9477
F src/sqliteInt.h 165409fa8adc8701148830804febeded3f2e4448
F src/sqliteLimit.h 164b0e6749d31e0daa1a4589a169d31c0dec7b3d
F src/status.c 4568e72dfd36b6a5911f93457364deb072e0b03a
F src/table.c 2cd62736f845d82200acfa1287e33feb3c15d62e
F src/tclsqlite.c de581e2e71f5e7f98366156afad83b4742ac6fe0
F src/test1.c 33b9c49f728cf28937eea7b246c28e89e3cf5e9e
F src/tclsqlite.c bd86070f52ae3f77a2e6b3b065ff03adb9140bfa
F src/test1.c 4cbabeb8b2c487f67d724e2ea03841b69fa640c4
F src/test2.c 80d323d11e909cf0eb1b6fbb4ac22276483bcf31
F src/test3.c 124ff9735fb6bb7d41de180d6bac90e7b1509432
F src/test4.c d1e5a5e904d4b444cf572391fdcb017638e36ff7
@@ -940,6 +940,7 @@ F test/whereC.test 13ff5ec0dba407c0e0c075980c75b3275a6774e5
F test/wherelimit.test 5e9fd41e79bb2b2d588ed999d641d9c965619b31
F test/win32lock.test b2a539e85ae6b2d78475e016a9636b4451dc7fb9
F test/zeroblob.test caaecfb4f908f7bc086ed238668049f96774d688
F test/zerodamage.test 0e12b2d7343f1fbb015e56a4a2a6074336ff46cf
F tool/build-shell.sh 12aa4391073a777fcb6dcc490b219a018ae98bac
F tool/diffdb.c 7524b1b5df217c20cd0431f6789851a4e0cb191b
F tool/extract.c 054069d81b095fbdc189a6f5d4466e40380505e2
@@ -984,7 +985,7 @@ F tool/tostr.awk e75472c2f98dd76e06b8c9c1367f4ab07e122d06
F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
F tool/warnings-clang.sh 9f406d66e750e8ac031c63a9ef3248aaa347ef2a
F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
P 92c73b421b6242b09247dfb759777a531a107523
R 0e9b80c28c07203b08d85530f30aefdc
P 7ac713a14e24c48651c2a97acc9839850fa7f3c3
R 8d88cdfbb2218ba883425a8ad72e347f
U drh
Z 960abf57a2870882cf541fd88a471911
Z 6c0db6cbcd8026c224cda9667bf4cff6

2
manifest.uuid
View File

@@ -1 +1 @@
7ac713a14e24c48651c2a97acc9839850fa7f3c3
c83627b73285f883719845c1b9fe85f378f28dd2

1
src/main.c
View File

@@ -2977,6 +2977,7 @@ int sqlite3_test_control(int op, ...){
** returns a NULL pointer.
*/
const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam){
if( zFilename==0 ) return 0;
zFilename += sqlite3Strlen30(zFilename) + 1;
while( zFilename[0] ){
int x = strcmp(zFilename, zParam);

64
src/os_unix.c
View File

@@ -215,13 +215,13 @@ struct unixFile {
int h; /* The file descriptor */
unsigned char eFileLock; /* The type of lock held on this fd */
unsigned char ctrlFlags; /* Behavioral bits. UNIXFILE_* flags */
unsigned char szSector; /* Sectorsize/512 */
int lastErrno; /* The unix errno from last I/O error */
void *lockingContext; /* Locking style specific state */
UnixUnusedFd *pUnused; /* Pre-allocated UnixUnusedFd */
const char *zPath; /* Name of the file */
unixShm *pShm; /* Shared memory segment information */
int szChunk; /* Configured by FCNTL_CHUNK_SIZE */
int szSector; /* Sector size */
#if SQLITE_ENABLE_LOCKING_STYLE
int openFlags; /* The flags specified at open() */
#endif
@@ -263,6 +263,7 @@ struct unixFile {
#else
# define UNIXFILE_DIRSYNC 0x00
#endif
#define UNIXFILE_ZERO_DAMAGE 0x10 /* True if SQLITE_IOCAP_ZERO_DAMAGE */
/*
** Include code that is common to all os_*.c files
@@ -3511,6 +3512,22 @@ static int fcntlSizeHint(unixFile *pFile, i64 nByte){
return SQLITE_OK;
}
/*
** If *pArg is inititially negative then this is a query. Set *pArg to
** 1 or 0 depending on whether or not bit mask of pFile->ctrlFlags is set.
**
** If *pArg is 0 or 1, then clear or set the mask bit of pFile->ctrlFlags.
*/
static void unixModeBit(unixFile *pFile, unsigned char mask, int *pArg){
if( *pArg<0 ){
*pArg = (pFile->ctrlFlags & mask)!=0;
}else if( (*pArg)==0 ){
pFile->ctrlFlags &= ~mask;
}else{
pFile->ctrlFlags |= mask;
}
}
/*
** Information and control of an open file handle.
*/
@@ -3537,14 +3554,11 @@ static int unixFileControl(sqlite3_file *id, int op, void *pArg){
return rc;
}
case SQLITE_FCNTL_PERSIST_WAL: {
int bPersist = *(int*)pArg;
if( bPersist<0 ){
*(int*)pArg = (pFile->ctrlFlags & UNIXFILE_PERSIST_WAL)!=0;
}else if( bPersist==0 ){
pFile->ctrlFlags &= ~UNIXFILE_PERSIST_WAL;
}else{
pFile->ctrlFlags |= UNIXFILE_PERSIST_WAL;
unixModeBit(pFile, UNIXFILE_PERSIST_WAL, (int*)pArg);
return SQLITE_OK;
}
case SQLITE_FCNTL_ZERO_DAMAGE: {
unixModeBit(pFile, UNIXFILE_ZERO_DAMAGE, (int*)pArg);
return SQLITE_OK;
}
case SQLITE_FCNTL_VFSNAME: {
@@ -3589,27 +3603,37 @@ static int unixSectorSize(sqlite3_file *pFile){
unixFile *p = (unixFile*)pFile;
if( p->szSector==0 ){
#ifdef MISSING_STATVFS
p->szSector = SQLITE_DEFAULT_SECTOR_SIZE;
p->szSector = SQLITE_DEFAULT_SECTOR_SIZE/512;
#else
struct statvfs x;
int sz;
memset(&x, 0, sizeof(x));
osStatvfs(p->zPath, &x);
p->szSector = sz = (int)x.f_frsize;
sz = (int)x.f_frsize;
if( sz<512 || sz>65536 || (sz&(sz-1))!=0 ){
p->szSector = SQLITE_DEFAULT_SECTOR_SIZE;
sz = SQLITE_DEFAULT_SECTOR_SIZE;
}
p->szSector = sz/512;
#endif
}
return p->szSector;
return p->szSector*512;
}
/*
** Return the device characteristics for the file. This is always 0 for unix.
** Return the device characteristics for the file.
**
** This VFS is set up to return SQLITE_IOCAP_ZERO_DAMAGE by default.
** However, that choice is contraversial sicne technically the underlying
** file system does not always provide ZERO_DAMAGE. (In other words, after
** a power-loss event, parts of the file that were never written might end
** up being altered.) However, non-ZERO-DAMAGE behavior is very, very rare.
** And asserting ZERO_DAMAGE makes a large reduction in the amount of required
** I/O. Hence, while ZERO_DAMAGE is on by default, there is a file-control
** available to turn it off.
*/
static int unixDeviceCharacteristics(sqlite3_file *NotUsed){
UNUSED_PARAMETER(NotUsed);
return SQLITE_IOCAP_ZERO_DAMAGE;
static int unixDeviceCharacteristics(sqlite3_file *id){
unixFile *p = (unixFile*)id;
return (p->ctrlFlags & UNIXFILE_ZERO_DAMAGE) ? SQLITE_IOCAP_ZERO_DAMAGE : 0;
}
#ifndef SQLITE_OMIT_WAL
@@ -4568,6 +4592,7 @@ static int fillInUnixFile(
const sqlite3_io_methods *pLockingStyle;
unixFile *pNew = (unixFile *)pId;
int rc = SQLITE_OK;
const char *zZeroDam; /* Value of the zero_damage query parameter */
assert( pNew->pInode==NULL );
@@ -4594,10 +4619,11 @@ static int fillInUnixFile(
pNew->h = h;
pNew->pVfs = pVfs;
pNew->zPath = zFilename;
zZeroDam = sqlite3_uri_parameter(zFilename, "zero_damage");
if( zZeroDam==0 ) zZeroDam = "1";
pNew->ctrlFlags = atoi(zZeroDam) ? UNIXFILE_ZERO_DAMAGE : 1;
if( memcmp(pVfs->zName,"unix-excl",10)==0 ){
pNew->ctrlFlags = UNIXFILE_EXCL;
}else{
pNew->ctrlFlags = 0;
pNew->ctrlFlags |= UNIXFILE_EXCL;
}
if( isReadOnly ){
pNew->ctrlFlags |= UNIXFILE_RDONLY;

41
src/os_win.c
View File

@@ -59,7 +59,7 @@ struct winFile {
HANDLE h; /* Handle for accessing the file */
u8 locktype; /* Type of lock currently held on this file */
short sharedLockByte; /* Randomly chosen byte used as a shared lock */
u8 bPersistWal; /* True to persist WAL files */
u8 ctrlFlags; /* Flags. See WINFILE_* below */
DWORD lastErrno; /* The Windows errno from the last I/O error */
DWORD sectorSize; /* Sector size of the device file is on */
winShm *pShm; /* Instance of shared memory on this file */
@@ -74,6 +74,12 @@ struct winFile {
#endif
};
/*
** Allowed values for winFile.ctrlFlags
*/
#define WINFILE_PERSIST_WAL 0x04 /* Persistent WAL mode */
#define WINFILE_ZERO_DAMAGE 0x10 /* True if SQLITE_IOCAP_ZERO_DAMAGE */
/*
* If compiled with SQLITE_WIN32_MALLOC on Windows, we will use the
* various Win32 API heap functions instead of our own.
@@ -2125,6 +2131,22 @@ static int winUnlock(sqlite3_file *id, int locktype){
return rc;
}
/*
** If *pArg is inititially negative then this is a query. Set *pArg to
** 1 or 0 depending on whether or not bit mask of pFile->ctrlFlags is set.
**
** If *pArg is 0 or 1, then clear or set the mask bit of pFile->ctrlFlags.
*/
static void winModeBit(winFile *pFile, unsigned char mask, int *pArg){
if( *pArg<0 ){
*pArg = (pFile->ctrlFlags & mask)!=0;
}else if( (*pArg)==0 ){
pFile->ctrlFlags &= ~mask;
}else{
pFile->ctrlFlags |= mask;
}
}
/*
** Control and query of the open file handle.
*/
@@ -2160,12 +2182,11 @@ static int winFileControl(sqlite3_file *id, int op, void *pArg){
return SQLITE_OK;
}
case SQLITE_FCNTL_PERSIST_WAL: {
int bPersist = *(int*)pArg;
if( bPersist<0 ){
*(int*)pArg = pFile->bPersistWal;
}else{
pFile->bPersistWal = bPersist!=0;
winModeBit(pFile, WINFILE_PERSIST_WAL, (int*)pArg);
return SQLITE_OK;
}
case SQLITE_FCNTL_ZERO_DAMAGE: {
winModeBit(pFile, WINFILE_ZERO_DAMAGE, (int*)pArg);
return SQLITE_OK;
}
case SQLITE_FCNTL_VFSNAME: {
@@ -2212,9 +2233,9 @@ static int winSectorSize(sqlite3_file *id){
** Return a vector of device characteristics.
*/
static int winDeviceCharacteristics(sqlite3_file *id){
UNUSED_PARAMETER(id);
winFile *p = (winFile*)id;
return SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN |
SQLITE_IOCAP_ZERO_DAMAGE;
((p->ctrlFlags & WINFILE_ZERO_DAMAGE)?SQLITE_IOCAP_ZERO_DAMAGE:0);
}
#ifndef SQLITE_OMIT_WAL
@@ -3004,6 +3025,7 @@ static int winOpen(
void *zConverted; /* Filename in OS encoding */
const char *zUtf8Name = zName; /* Filename in UTF-8 encoding */
int cnt = 0;
const char *zZeroDam; /* Value of zero_damage query parameter */
/* If argument zPath is a NULL pointer, this function is required to open
** a temporary file. Use this buffer to store the file name in.
@@ -3179,6 +3201,9 @@ static int winOpen(
pFile->pVfs = pVfs;
pFile->pShm = 0;
pFile->zPath = zName;
zZeroDam = sqlite3_uri_parameter(zName, "zero_damage");
if( zZeroDam==0 ) zZeroDam = "1";
pFile->ctrlFlags = atoi(zZeroDam) ? WINFILE_ZERO_DAMAGE : 1;
pFile->sectorSize = getSectorSize(pVfs, zUtf8Name);
#if SQLITE_OS_WINCE

10
src/sqlite.h.in
View File

@@ -774,6 +774,15 @@ struct sqlite3_io_methods {
** WAL mode. If the integer is -1, then it is overwritten with the current
** WAL persistence setting.
**
** ^The [SQLITE_FCNTL_ZERO_DAMAGE] opcode is used to set or query the
** persistent zero-damage setting. The zero-damage setting determines
** the [SQLITE_IOCAP_ZERO_DAMAGE] bit of the xDeviceCharacteristics methods.
** The fourth parameter to
** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
** mode. If the integer is -1, then it is overwritten with the current
** zero-damage mode setting.
**
** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
** a write transaction to indicate that, unless it is rolled back for some
** reason, the entire database file will be overwritten by the current
@@ -802,6 +811,7 @@ struct sqlite3_io_methods {
#define SQLITE_FCNTL_PERSIST_WAL 10
#define SQLITE_FCNTL_OVERWRITE 11
#define SQLITE_FCNTL_VFSNAME 12
#define SQLITE_FCNTL_ZERO_DAMAGE 13
/*
** CAPI3REF: Mutex Handle

8
src/tclsqlite.c
View File

@@ -3001,6 +3001,14 @@ static int DbMain(void *cd, Tcl_Interp *interp, int objc,Tcl_Obj *const*objv){
}else{
flags &= ~SQLITE_OPEN_FULLMUTEX;
}
}else if( strcmp(zArg, "-uri")==0 ){
int b;
if( Tcl_GetBooleanFromObj(interp, objv[i+1], &b) ) return TCL_ERROR;
if( b ){
flags |= SQLITE_OPEN_URI;
}else{
flags &= ~SQLITE_OPEN_URI;
}
}else{
Tcl_AppendResult(interp, "unknown option: ", zArg, (char*)0);
return TCL_ERROR;

33
src/test1.c
View File

@@ -5235,6 +5235,38 @@ static int file_control_persist_wal(
return TCL_OK;
}
/*
** tclcmd: file_control_zero_damage DB ZERO-DAMAGE-FLAG
**
** This TCL command runs the sqlite3_file_control interface with
** the SQLITE_FCNTL_ZERO_DAMAGE opcode.
*/
static int file_control_zero_damage(
ClientData clientData, /* Pointer to sqlite3_enable_XXX function */
Tcl_Interp *interp, /* The TCL interpreter that invoked this command */
int objc, /* Number of arguments */
Tcl_Obj *CONST objv[] /* Command arguments */
){
sqlite3 *db;
int rc;
int bDamage;
char z[100];
if( objc!=3 ){
Tcl_AppendResult(interp, "wrong # args: should be \"",
Tcl_GetStringFromObj(objv[0], 0), " DB FLAG", 0);
return TCL_ERROR;
}
if( getDbPointer(interp, Tcl_GetString(objv[1]), &db) ){
return TCL_ERROR;
}
if( Tcl_GetIntFromObj(interp, objv[2], &bDamage) ) return TCL_ERROR;
rc = sqlite3_file_control(db, NULL, SQLITE_FCNTL_ZERO_DAMAGE,(void*)&bDamage);
sqlite3_snprintf(sizeof(z), z, "%d %d", rc, bDamage);
Tcl_AppendResult(interp, z, (char*)0);
return TCL_OK;
}
/*
** tclcmd: file_control_vfsname DB ?AUXDB?
@@ -6093,6 +6125,7 @@ int Sqlitetest1_Init(Tcl_Interp *interp){
{ "file_control_sizehint_test", file_control_sizehint_test, 0 },
{ "file_control_win32_av_retry", file_control_win32_av_retry, 0 },
{ "file_control_persist_wal", file_control_persist_wal, 0 },
{ "file_control_zero_damage", file_control_zero_damage, 0 },
{ "file_control_vfsname", file_control_vfsname, 0 },
{ "sqlite3_vfs_list", vfs_list, 0 },
{ "sqlite3_create_function_v2", test_create_function_v2, 0 },

109
test/zerodamage.test Normal file
View File

@@ -0,0 +1,109 @@
# 2011 December 21
#
# The author disclaims copyright to this source code. In place of
# a legal notice, here is a blessing:
#
# May you do good and not evil.
# May you find forgiveness for yourself and forgive others.
# May you share freely, never taking more than you give.
#
#***********************************************************************
#
# This file implements tests of the SQLITE_IOCAP_ZERO_DAMAGE property
# and the SQLITE_FCNTL_ZERO_DAMAGE file-control for manipulating it.
#
set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix wal5
# ZERO_DAMAGE defaults to true
#
do_test zerodamage-1.0 {
file_control_zero_damage db -1
} {0 1}
# Check the ability to turn zero-damage on and off.
#
do_test zerodamage-1.1 {
file_control_zero_damage db 0
file_control_zero_damage db -1
} {0 0}
do_test zerodamage-1.2 {
file_control_zero_damage db 1
file_control_zero_damage db -1
} {0 1}
# Run a transaction with zero-damage on, a small page size and a much larger
# sectorsize. Verify that the maximum journal size is small - that the
# rollback journal is not being padded.
#
do_test zerodamage-2.0 {
db close
testvfs tv -default 1
tv sectorsize 8192
sqlite3 db file:test.db?zero_damage=1 -uri 1
unset -nocomplain ::max_journal_size
set ::max_journal_size 0
proc xDeleteCallback {method file args} {
set sz [file size $file]
if {$sz>$::max_journal_size} {set ::max_journal_size $sz}
}
tv filter xDelete
tv script xDeleteCallback
register_wholenumber_module db
db eval {
PRAGMA page_size=1024;
PRAGMA journal_mode=DELETE;
PRAGMA cache_size=5;
CREATE VIRTUAL TABLE nums USING wholenumber;
CREATE TABLE t1(x, y);
INSERT INTO t1 SELECT value, randomblob(100) FROM nums
WHERE value BETWEEN 1 AND 400;
}
set ::max_journal_size 0
db eval {
UPDATE t1 SET y=randomblob(50) WHERE x=123;
}
concat [file_control_zero_damage db -1] [set ::max_journal_size]
} {0 1 2576}
# Repeat the previous step with zero-damage turned off. This time the
# maximum rollback journal size should be much larger.
#
do_test zerodamage-2.1 {
set ::max_journal_size 0
db close
sqlite3 db file:test.db?zero_damage=0 -uri 1
db eval {
UPDATE t1 SET y=randomblob(50) WHERE x=124;
}
concat [file_control_zero_damage db -1] [set ::max_journal_size]
} {0 0 24704}
# Run a WAL-mode transaction with ZERO_DAMAGE on to verify that the
# WAL file does not get too big.
#
do_test zerodamage-3.0 {
db eval {
PRAGMA journal_mode=WAL;
}
db close
sqlite3 db file:test.db?zero_damage=1 -uri 1
db eval {
UPDATE t1 SET y=randomblob(50) WHERE x=124;
}
file size test.db-wal
} {1080}
# Repeat the previous with ZERO_DAMAGE off. Verify that the WAL file
# is padded.
#
do_test zerodamage-3.1 {
db close
sqlite3 db file:test.db?zero_damage=0 -uri 1
db eval {
UPDATE t1 SET y=randomblob(50) WHERE x=124;
}
file size test.db-wal
} {8416}