bsp;a database, the following error messages may display:
Error 3115 Severity 10: User %.*s in database %.*s has suid %d, which is the same as the suid of the DBO (as defined in Sysdatabases). User %.*s will be given suid %d.
Error 3116 Severity 10: When all load transactions have been completed for database %.*s, user %.*s should be given a unique suid.
These errors occur due to a condition that causes inconsistency in the user information between source and target databases. The load attempts to update sysusers..suid for the target database to match the source suid. However, doing this would cause duplicate suids in sysusers, which is not allowed because there is a uniqueness requirement for suid.
Example 1
This example shows sysusers before the load and after:
sysusers suid uid name
Before Load 23 1 dbo sa_user
1 2
After Load 1 1 dbo sa_user
-99 2
In this case, another user owned the database that was dumped but had the "sa" role as a user in the database. The destination database for the load was created by the "sa". The sysusers row for "dbo" should be changed at the end of the load. There is a unique index on suid, so the row for sa_user has its suid changed to -99.
Why do I get Error 3114 after loading dump of master to another machine?
You may encounter this error:
Error 3114, Severity: 21, State: 1 Database does not have an entry in Sysdatabases.
Cannot recover the master database, exiting.
The master database contains references to the devices and databases that are loaded onto the first machine. The second machine contains the wrong references, causing the error. Sybase recommends using the same machine for dumps and loads of the master database.
Backups and Maintenance
Why should I run dbcc commands on a database before dumping?
It is often possible to dump a database that is not consistent. The dbcc checkalloc, dbcc checkdb, dbcc checkcatalog, and dbcc checkstorage commands perform different tests of the database's consistency; they are briefly described in the chapter, "Checking Database Consistency" in the Sybase Adaptive ServerTM Enterprise System Administration Guide. When it is not practical to run all these commands before each dump of a very large database, they should all be run periodically as part of a preventive maintenance program
Note: dbcc checkstorage, introduced in Adaptive Server 11.5, requires its own database, dbccdb.
How often should I perform dbcc?
How often depends on how much data you are willing to lose in a worst-case scenario. In general, the more important your data, the more often you should run dbccs.
If yours is not a 24-hour organization, and dbccs will complete during your down-time, perform them nightly with the output redirected to a file. Perform a grep on the file for the keywords "Err," "err," and "Msg" to catch most errors that dbcc would report. Scan the output occasionally to catch anything else that might be reported.
Mission-critical enterprises often use a second server as a "warm backup." Instead of running dbcc commands on the production server, dumps are taken, loaded on the warm backup, and dbccs are run there. If errors are discovered, attempts are made to correct it on production server.
Sites with very large databases sometimes use a rotating schedule of dbcc tablealloc and dbcc checktables, rather than the all-at-once dbcc checkalloc and dbcc checkdbs. Additionally, a new command, dbcc checkstorage, allows you to check a database that is in use with little impact on performance. See the Sybase Adaptive ServerTM Enterprise System Administration Guide.
How often should I dump and load the database?
In case of catastrophe (such as disk failure), how much processing are you willing to lose? If the answer is 1 hour's worth, you probably should dump the database at least daily, and dump the log at least hourly.
Generally, you load the database to recover from catastrophe. However, Sybase recommends you occasionally perform a database dump and load in a test environment to ensure that the dump process is working and you are familiar with how to do it.
Note: Do not perform these tests on your production database. If something is wrong with your dump, and you load it on top of your database, then you have lost your data.
Which utility should I use for nightly tape backups?
In addition to the server commands dump database and dump tran, you can use third-party tools such as SQL-BacktrackTM.
Which media drivers are compatible with the server?
Because of the number of media drivers, Sybase does not test compatibility for every driver. Contact your vendor for driver-compatibility information.
What if I don't have enough time for a full backup?
You can shorten the required backup-time by:
Truncating the log just before performing dump database. A database dump includes all log pages, regardless of whether they are committed records. By truncating the log, only uncommitted records will be included.
Stripe the dump over as many dump devices as possible. Backup Server can handle up to 32 dump devices.
If neither of these measures help, you can still perform full backups. Backup Server is designed to minimize interference with server operation. Therefore, you can perform du
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