When writing to an FTS table, take an exclusive shared-cache lock on the %_segdir table before writing. Otherwise, an xCommit() call may report an SQLITE_LOCKED error.

FossilOrigin-Name: 3cd2da42e9403b1e6243ad53f3f2bbf89c0fb9b0
This commit is contained in:
dan 2013-05-27 10:11:53 +00:00
parent 40b521f847
commit 87ddfeb079
6 changed files with 137 additions and 39 deletions

View File

@ -2984,11 +2984,7 @@ static int fts3FilterMethod(
return rc;
}
rc = sqlite3Fts3ReadLock(p);
if( rc!=SQLITE_OK ) return rc;
rc = fts3EvalStart(pCsr);
sqlite3Fts3SegmentsClose(p);
if( rc!=SQLITE_OK ) return rc;
pCsr->pNextId = pCsr->aDoclist;

View File

@ -489,37 +489,30 @@ static void fts3SqlExec(
/*
** This function ensures that the caller has obtained a shared-cache
** table-lock on the %_content table. This is required before reading
** data from the fts3 table. If this lock is not acquired first, then
** the caller may end up holding read-locks on the %_segments and %_segdir
** tables, but no read-lock on the %_content table. If this happens
** a second connection will be able to write to the fts3 table, but
** attempting to commit those writes might return SQLITE_LOCKED or
** SQLITE_LOCKED_SHAREDCACHE (because the commit attempts to obtain
** write-locks on the %_segments and %_segdir ** tables).
** This function ensures that the caller has obtained an exclusive
** shared-cache table-lock on the %_segdir table. This is required before
** writing data to the fts3 table. If this lock is not acquired first, then
** the caller may end up attempting to take this lock as part of committing
** a transaction, causing SQLite to return SQLITE_LOCKED or
** LOCKED_SHAREDCACHEto a COMMIT command.
**
** We try to avoid this because if FTS3 returns any error when committing
** a transaction, the whole transaction will be rolled back. And this is
** not what users expect when they get SQLITE_LOCKED_SHAREDCACHE. It can
** still happen if the user reads data directly from the %_segments or
** %_segdir tables instead of going through FTS3 though.
**
** This reasoning does not apply to a content=xxx table.
** It is best to avoid this because if FTS3 returns any error when
** committing a transaction, the whole transaction will be rolled back.
** And this is not what users expect when they get SQLITE_LOCKED_SHAREDCACHE.
** It can still happen if the user locks the underlying tables directly
** instead of accessing them via FTS.
*/
int sqlite3Fts3ReadLock(Fts3Table *p){
int rc; /* Return code */
sqlite3_stmt *pStmt; /* Statement used to obtain lock */
if( p->zContentTbl==0 ){
rc = fts3SqlStmt(p, SQL_SELECT_CONTENT_BY_ROWID, &pStmt, 0);
static int fts3Writelock(Fts3Table *p){
int rc = SQLITE_OK;
if( p->nPendingData==0 ){
sqlite3_stmt *pStmt;
rc = fts3SqlStmt(p, SQL_DELETE_SEGDIR_LEVEL, &pStmt, 0);
if( rc==SQLITE_OK ){
sqlite3_bind_null(pStmt, 1);
sqlite3_step(pStmt);
rc = sqlite3_reset(pStmt);
}
}else{
rc = SQLITE_OK;
}
return rc;
@ -5297,6 +5290,9 @@ int sqlite3Fts3UpdateMethod(
aSzIns = &aSzDel[p->nColumn+1];
memset(aSzDel, 0, sizeof(aSzDel[0])*(p->nColumn+1)*2);
rc = fts3Writelock(p);
if( rc!=SQLITE_OK ) goto update_out;
/* If this is an INSERT operation, or an UPDATE that modifies the rowid
** value, then this operation requires constraint handling.
**

View File

@ -1,5 +1,5 @@
C Set\s_XOPEN_SOURCE\sto\s600\sso\sthat\sfchmod()\swill\s(hopefully)\swork\son\sFreeBSD.
D 2013-05-24T12:47:26.703
C When\swriting\sto\san\sFTS\stable,\stake\san\sexclusive\sshared-cache\slock\son\sthe\s%_segdir\stable\sbefore\swriting.\sOtherwise,\san\sxCommit()\scall\smay\sreport\san\sSQLITE_LOCKED\serror.
D 2013-05-27T10:11:53.308
F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
F Makefile.in f6b58b7bdf6535f0f0620c486dd59aa4662c0b4f
F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@ -55,7 +55,7 @@ F ext/fts3/README.content fdc666a70d5257a64fee209f97cf89e0e6e32b51
F ext/fts3/README.syntax a19711dc5458c20734b8e485e75fb1981ec2427a
F ext/fts3/README.tokenizers e0a8b81383ea60d0334d274fadf305ea14a8c314
F ext/fts3/README.txt 8c18f41574404623b76917b9da66fcb0ab38328d
F ext/fts3/fts3.c 4bc160e6ff9ab5456b600f389f8941485ea5082f
F ext/fts3/fts3.c 931b3c83abdd1ab3bb389b2130431c2a9ff73b91
F ext/fts3/fts3.h 3a10a0af180d502cecc50df77b1b22df142817fe
F ext/fts3/fts3Int.h 0b167bed9e63151635620a4f639bc62ac6012cba
F ext/fts3/fts3_aux.c b02632f6dd0e375ce97870206d914ea6d8df5ccd
@ -73,7 +73,7 @@ F ext/fts3/fts3_tokenizer.h 64c6ef6c5272c51ebe60fc607a896e84288fcbc3
F ext/fts3/fts3_tokenizer1.c 5c98225a53705e5ee34824087478cf477bdb7004
F ext/fts3/fts3_unicode.c 92391b4b4fb043564c6539ea9b8661e3bcba47b9
F ext/fts3/fts3_unicode2.c a863f05f758af36777dffc2facc898bc73fec896
F ext/fts3/fts3_write.c d92c6cbe07363791cfe8b62b4dee67e6f8afc9e2
F ext/fts3/fts3_write.c 6a1fc0e922e76b68e594bf7bc33bac72af9dc47b
F ext/fts3/fts3speed.tcl b54caf6a18d38174f1a6e84219950d85e98bb1e9
F ext/fts3/mkfts3amal.tcl 252ecb7fe6467854f2aa237bf2c390b74e71f100
F ext/fts3/tool/fts3view.c 6cfc5b67a5f0e09c0d698f9fd012c784bfaa9197
@ -513,7 +513,7 @@ F test/fts3prefix.test b36d4f00b128a51e7b386cc013a874246d9d7dc1
F test/fts3prefix2.test 477ca96e67f60745b7ac931cfa6e9b080c562da5
F test/fts3query.test ef79d31fdb355d094baec1c1b24b60439a1fb8a2
F test/fts3rnd.test 1320d8826a845e38a96e769562bf83d7a92a15d0
F test/fts3shared.test 8bb266521d7c5495c0ae522bb4d376ad5387d4a2
F test/fts3shared.test c2f60e152e8554549eb25f0a7593ea01389c5037
F test/fts3snippet.test 8e956051221a34c7daeb504f023cb54d5fa5a8b2
F test/fts3sort.test 95be0b19d7e41c44b29014f13ea8bddd495fd659
F test/fts3tok1.test 4d9e7401679dc71f6b2f76416309b923210bfdbe
@ -924,7 +924,7 @@ F test/tkt3997.test a335fa41ca3985660a139df7b734a26ef53284bd
F test/tkt4018.test 7c2c9ba4df489c676a0a7a0e809a1fb9b2185bd1
F test/tokenize.test ce430a7aed48fc98301611429595883fdfcab5d7
F test/trace.test 4b36a41a3e9c7842151af6da5998f5080cdad9e5
F test/trace2.test c1dc104a8d11a347c870cfea6235e3fc6f6cb06d
F test/trace2.test e7a988fdd982cdec62f1f1f34b0360e6476d01a0
F test/trans.test 6e1b4c6a42dba31bd65f8fa5e61a2708e08ddde6
F test/trans2.test d5337e61de45e66b1fcbf9db833fa8c82e624b22
F test/trans3.test 373ac5183cc56be69f48ae44090e7f672939f732
@ -1066,7 +1066,7 @@ F tool/vdbe-compress.tcl f12c884766bd14277f4fcedcae07078011717381
F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
F tool/win/sqlite.vsix 97894c2790eda7b5bce3cc79cb2a8ec2fde9b3ac
P 9e2c17c5358b156b588542dbba38da7fedf5302b
R 447bfb9d68d03e84058ef9e235e367ce
U drh
Z 0a3675dfa27f37f077377df6c72c7598
P 61a10452399db28cd5ea4ba9d416b87a34c2eddb
R 5b2b7d523083ab3d77d86c0cce4d267d
U dan
Z 5b590f475035536f2f371b845c79a1e4

View File

@ -1 +1 @@
61a10452399db28cd5ea4ba9d416b87a34c2eddb
3cd2da42e9403b1e6243ad53f3f2bbf89c0fb9b0

View File

@ -1,3 +1,4 @@
#
# 2010 September 17
#
# May you do good and not evil.
@ -5,6 +6,9 @@
# May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library. The
# focus of this file is the interactions between the FTS3/4 module
# and shared-cache mode.
#
set testdir [file dirname $argv0]
@ -14,6 +18,7 @@ ifcapable !fts3||!shared_cache {
finish_test
return
}
set ::testprefix fts3shared
db close
set ::enable_shared_cache [sqlite3_enable_shared_cache 1]
@ -67,6 +72,106 @@ do_test fts3shared-1.6 { sqlite3_get_autocommit db2 } 0
db close
db2 close
#-------------------------------------------------------------------------
# The following tests - fts3shared-2.* - test that unless FTS is bypassed
# and the underlying tables accessed directly, it is not possible for an
# SQLITE_LOCKED error to be enountered when committing an FTS transaction.
#
# Any SQLITE_LOCKED error should be returned when the fts4 (or fts4aux)
# table is first read/written within a transaction, not later on.
#
set LOCKED {1 {database table is locked}}
forcedelete test.db
sqlite3 dbR test.db
sqlite3 dbW test.db
do_test 2.1 {
execsql {
CREATE VIRTUAL TABLE t1 USING fts4;
CREATE TABLE t2ext(a, b);
CREATE VIRTUAL TABLE t2 USING fts4(content=t2ext);
CREATE VIRTUAL TABLE t1aux USING fts4aux(t1);
CREATE VIRTUAL TABLE t2aux USING fts4aux(t2);
INSERT INTO t1 VALUES('a b c');
INSERT INTO t2(rowid, a, b) VALUES(1, 'd e f', 'g h i');
} dbW
} {}
# Test that once [dbW] has written to the FTS table, no client may read
# from the FTS or fts4aux table.
do_test 2.2.1 {
execsql {
BEGIN;
INSERT INTO t1 VALUES('j k l');
} dbW
execsql BEGIN dbR
} {}
do_test 2.2.2 { catchsql "SELECT * FROM t1 WHERE rowid=1" dbR } $LOCKED
do_test 2.2.3 { catchsql "SELECT * FROM t1 WHERE t1 MATCH 'a'" dbR } $LOCKED
do_test 2.2.4 { catchsql "SELECT rowid FROM t1 WHERE t1 MATCH 'a'" dbR } $LOCKED
do_test 2.2.5 { catchsql "SELECT * FROM t1" dbR } $LOCKED
do_test 2.2.6 { catchsql "SELECT * FROM t1aux" dbR } $LOCKED
do_test 2.2.7 { execsql COMMIT dbW } {}
do_test 2.2.8 { execsql COMMIT dbR } {}
# Same test as 2.2.*, except with a content= table.
#
do_test 2.3.1 {
execsql {
BEGIN;
INSERT INTO t2(rowid, a, b) VALUES(2, 'j k l', 'm n o');
} dbW
execsql BEGIN dbR
} {}
do_test 2.3.3 { catchsql "SELECT * FROM t2 WHERE t2 MATCH 'a'" dbR } $LOCKED
do_test 2.3.4 { catchsql "SELECT rowid FROM t2 WHERE t2 MATCH 'a'" dbR } $LOCKED
do_test 2.3.6 { catchsql "SELECT * FROM t2aux" dbR } $LOCKED
do_test 2.3.7 { execsql COMMIT dbW } {}
do_test 2.3.8 { execsql COMMIT dbR } {}
# Test that once a connection has read from the FTS or fts4aux table,
# another connection may not write to the FTS table.
#
foreach {tn sql} {
1 "SELECT * FROM t1 WHERE rowid=1"
2 "SELECT * FROM t1 WHERE t1 MATCH 'a'"
3 "SELECT rowid FROM t1 WHERE t1 MATCH 'a'"
4 "SELECT * FROM t1"
5 "SELECT * FROM t1aux"
} {
do_test 2.4.$tn {
execsql BEGIN dbR
execsql $::sql dbR
execsql BEGIN dbW
catchsql "INSERT INTO t1 VALUES('p q r')" dbW
} $LOCKED
execsql ROLLBACK dbR
execsql ROLLBACK dbW
}
# Same test as 2.4.*, except with a content= table.
#
foreach {tn sql} {
2 "SELECT * FROM t2 WHERE t2 MATCH 'a'"
3 "SELECT rowid FROM t2 WHERE t2 MATCH 'a'"
5 "SELECT * FROM t2aux"
} {
do_test 2.5.$tn {
execsql BEGIN dbR
execsql $::sql dbR
execsql BEGIN dbW
catchsql "INSERT INTO t2(rowid, a, b) VALUES(3, 's t u', 'v w x')" dbW
} $LOCKED
execsql ROLLBACK dbR
execsql ROLLBACK dbW
}
dbW close
dbR close
sqlite3_enable_shared_cache $::enable_shared_cache
finish_test

View File

@ -128,6 +128,7 @@ ifcapable fts3 {
INSERT INTO x1 VALUES('North northwest wind between 8 and 14 mph');
} {
"INSERT INTO x1 VALUES('North northwest wind between 8 and 14 mph');"
"-- DELETE FROM 'main'.'x1_segdir' WHERE level = ?"
"-- INSERT INTO 'main'.'x1_content' VALUES(?,(?))"
"-- REPLACE INTO 'main'.'x1_docsize' VALUES(?,?)"
"-- SELECT value FROM 'main'.'x1_stat' WHERE id=?"