X-Received: by 10.43.141.196 with SMTP id jf4mr1945439icc.9.1398426124685; Fri, 25 Apr 2014 04:42:04 -0700 (PDT) X-Received: by 10.140.21.233 with SMTP id 96mr27304qgl.19.1398426124634; Fri, 25 Apr 2014 04:42:04 -0700 (PDT) Path: csiph.com!newsfeed.hal-mli.net!feeder3.hal-mli.net!peer02.iad.highwinds-media.com!news.highwinds-media.com!feed-me.highwinds-media.com!c1no3467209igq.0!news-out.google.com!du2ni15315qab.0!nntp.google.com!cm18no6218896qab.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail Newsgroups: comp.databases.ms-sqlserver Date: Fri, 25 Apr 2014 04:42:04 -0700 (PDT) In-Reply-To: Complaints-To: groups-abuse@google.com Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=195.57.19.36; posting-account=jIl9nQoAAAA9P37IIqQq64yAx-2NQYiu NNTP-Posting-Host: 195.57.19.36 References: User-Agent: G2/1.0 MIME-Version: 1.0 Message-ID: Subject: Re: power loss DB corruption From: bradbury9 Injection-Date: Fri, 25 Apr 2014 11:42:04 +0000 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable X-Received-Bytes: 2703 X-Received-Body-CRC: 4259211364 Xref: csiph.com comp.databases.ms-sqlserver:1741 El viernes, 25 de abril de 2014 12:24:40 UTC+2, Erland Sommarskog escribi= =F3: > Hendrik van der Heijden (hvdh@gmx.de) writes: >=20 > > I have a standard consumer PC (single SATA drive on Intel Chipset >=20 > > Controller) running Windows 7 and MS SQL Server 2012 Express. >=20 > >=20 >=20 > > When I load the database with transactions and pull the PC power cord, >=20 > > due to ACID compliance, I expect to get no data loss on reportedly >=20 > > completed transactions. However, on SQL Server 2012 very often the >=20 > > database is corrupt afterwards and cannot be used anymore. >=20 >=20 >=20 > If you pull the power cord, there are some risk for incomplete writes,=20 >=20 > isn't there? Should not happen if Sql Server is full ACID compilant and it claims to be = since SQL Server 2010. http://technet.microsoft.com/en-us/library/aa213068(v=3Dsql.80).aspx >=20 >=20 > What is important if you want to minimize data loss is to use the full=20 >=20 > recovery model and frequent transaction log backups. >=20 >=20 > Note that if the data file is damaged in case of a power outage, but=20 >=20 > the log file is not, you can recover the database by taking a tail-of- >=20 > the-log backup. If the log file is damaged, the prospects are bleaker, >=20 > even if the database is not. >=20 Good point, don't trust totally in ACID compilance. A good backup policy as= the above described should always happen. Please, note that I am *not* saying that Hendrik is not doing proper backup= s. ;-)