Monday, July 27, 2009

SQL 2008 compared to other RDBMS vendors

Just came across these links, hope it helps in making any decisions or migration...

SQL Server 2008 Vs MySQL
http://www.microsoft.com/sqlserver/2008/en/us/compare-mysql.aspx

SQL Server 2008 Vs IBM DB2
http://www.microsoft.com/sqlserver/2008/en/us/compare-ibm-db2.aspx

SQL Server 2008 Vs Oracle
http://www.microsoft.com/sqlserver/2008/en/us/compare-oracle.aspx

Wednesday, July 8, 2009

SQL server recovery models

SQL Server has 3 recovery model types which control types of backups so let’s discuss in more details all recovery types

when you do these operation sequential

right click any database—> properties –> select Pages –> options

you will see the dialog bellow

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as you see in fig above you have 3 types

the relationship between backup types(Rows Headers) and Recovery Models(Columns Header) are

  Full Bulk-logged Simple
Full Backup Yes Yes Yes
Differential Backup Yes Yes Yes
Transaction Backup Yes Yes No

it’s very clear that you can’t make trasaction log backup in simple mode.

so what is the Differential between Full mode and Bulk-Logged mode?

Full mode log any transaction in Transaction log file but Bulk-logged can’t log huge transaction to log file like bulk insert or create index in huge tables

you can use Bulk logged for more performance to insert bulk data to database because in this mode you will not log in  transaction log.

you can use Full mode to log any small things to transaction log file to feel safe when to return to end point of disaster