Hi everyone, I'm trying to track down some lost commits for SQLite 3.7.7.1 via the APSW Python wrapper. Pagesize etc. are all left at defaults for the APSW wrapper.
The following probablematic scenario: The sqlite db file and WAL/SHM files are on some automounted linux SAN filesystem (probably NFS beneath it), pretty old SLES 9 system with kernel 2.6.5-7.244-smp and pretty normal mount options for the filesystem. I now have SAN snapshots of two sets of sqlite.db and sqlite.db-wal/shm files from two consecutive days. The only change is in the WAL file, the sqlite.db file is totally unchanged (checked via md5sum and fs timestamps). In the snapshot form day 1 i see a commit, when executing a query. In the snapshot from day 2 the same entry is gone. I'm pretty sure there was no DELETE for the missing object, but want to verify what happend by comparing the WAL files. Now i checked the wal with the tool/showwal.c program from the source distribution and see differences in the frames 50-91 of 288 total frames, so basically in the middle of the file. Now my questions: Is it a sign of file corruption that some frames in the middle of the WAL file are differing between those two snapshots? >From the description how the WAL file works, i would assume that only new frames are appended, but old frames are never modified. My current assumption is, that some WAL journal writes were lost or messed up by the filesystem/SAN mount somehow, but i need to verify my assumptions about how WAL works first. Michael -- Michael Schlenker Software Architect CONTACT Software GmbH Tel.: +49 (421) 20153-80 Wiener Straße 1-3 Fax: +49 (421) 20153-41 28359 Bremen http://www.contact.de/ E-Mail: m...@contact.de Sitz der Gesellschaft: Bremen Geschäftsführer: Karl Heinz Zachries, Ralf Holtgrefe Eingetragen im Handelsregister des Amtsgerichts Bremen unter HRB 13215 _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
