On Mon, Dec 7, 2015 at 5:31 PM, Igor Tandetnik <igor at tandetnik.org> wrote: > On 12/7/2015 5:05 PM, Patrick Donnelly wrote: >> >> No rows were inserted but there are several writes. This behavior >> seems to be caused by AUTOINCREMENT? > > > Could be creating sqlite_sequence table where there wasn't one before. I > wonder if there are still writes on the second and subsequent no-op inserts.
There are still writes: CREATE TABLE t1(a INTEGER PRIMARY KEY AUTOINCREMENT, b integer); INSERT INTO t1(b) VALUES (1); select * from sqlite_sequence; .print --------------------------------- INSERT INTO t1 (b) SELECT 0 WHERE 1 = 0; select changes(); $ rm foo.db*; ./sqlite3 -vfstrace foo.db < test.sql ... t1|1 --------------------------------- trace.xLock(foo.db,SHARED) -> SQLITE_OK trace.xAccess("/home/batrick/sqlite-amalgamation-3090200/foo.db-journal",0) -> SQLITE_OK, out=0 trace.xFileSize(foo.db) -> SQLITE_OK, size=3072 trace.xRead(foo.db,n=16,ofst=24) -> SQLITE_OK trace.xFileSize(foo.db) -> SQLITE_OK, size=3072 trace.xAccess("/home/batrick/sqlite-amalgamation-3090200/foo.db-wal",0) -> SQLITE_OK, out=0 trace.xFileSize(foo.db) -> SQLITE_OK, size=3072 trace.xLock(foo.db,RESERVED) -> SQLITE_OK trace.xFileControl(foo.db,20) -> SQLITE_OK trace.xOpen(foo.db-journal,flags=0x806) -> SQLITE_OK trace.xDeviceCharacteristics(foo.db) -> 0x00001000 trace.xWrite(foo.db-journal,n=512,ofst=0) -> SQLITE_OK trace.xWrite(foo.db-journal,n=4,ofst=512) -> SQLITE_OK trace.xWrite(foo.db-journal,n=1024,ofst=516) -> SQLITE_OK trace.xWrite(foo.db-journal,n=4,ofst=1540) -> SQLITE_OK trace.xLock(foo.db,EXCLUSIVE) -> SQLITE_OK trace.xWrite(foo.db-journal,n=4,ofst=1544) -> SQLITE_OK trace.xWrite(foo.db-journal,n=1024,ofst=1548) -> SQLITE_OK trace.xWrite(foo.db-journal,n=4,ofst=2572) -> SQLITE_OK trace.xDeviceCharacteristics(foo.db) -> 0x00001000 trace.xRead(foo.db-journal,n=8,ofst=3072) -> SQLITE_IOERR_SHORT_READ trace.xSync(foo.db-journal,FULL) -> 0 trace.xWrite(foo.db-journal,n=12,ofst=0) -> SQLITE_OK trace.xSync(foo.db-journal,FULL) -> 0 trace.xWrite(foo.db,n=1024,ofst=0) -> SQLITE_OK trace.xWrite(foo.db,n=1024,ofst=2048) -> SQLITE_OK trace.xFileControl(foo.db,21) -> 12 trace.xSync(foo.db,FULL) -> 0 trace.xClose(foo.db-journal) -> SQLITE_OK trace.xDelete("/home/batrick/sqlite-amalgamation-3090200/foo.db-journal",0) -> SQLITE_OK trace.xFileControl(foo.db,22) -> 12 trace.xUnlock(foo.db,SHARED) -> SQLITE_OK trace.xDeviceCharacteristics(foo.db) -> 0x00001000 trace.xUnlock(foo.db,NONE) -> SQLITE_OK 0 trace.xDeviceCharacteristics(foo.db) -> 0x00001000 trace.xUnlock(foo.db,NONE) -> SQLITE_OK trace.xClose(foo.db) -> SQLITE_OK -- Patrick Donnelly