Like the upgrade process from SQL Server 2000 to SQL Server 2005, when upgrading SQL Server 2005 to SQL Server 2008 you have to upgrade to the edition you’re currently running or higher. For example, you can’t upgrade to SQL Server 2008 Standard Edition from SQL Server 2005 Enterprise Edition. Instead, if you have SQL Server 2005 Enterprise Edition installed, you have to upgrade to SQL Server 2008 Enterprise Edition. After you’ve selected the instance you want to upgrade from the drop-down menu, click Next.
On the next screen, you’ll see the features list. If there are any features that aren’t already selected that you want to install, select them here. Figure 3 shows that you’re installing the SQL Server engine, the Full Text Search feature, and the SQL Server Replication feature.
After making any changes that are needed, click Next, which will take you to the Instance Configuration screen. On this screen, which will appear to be pretty redundant because it’s a recap of the information shown in Figure 2, you can verify the instance that will be upgraded, and then click Next.
Then you’ll see the Disk Space Requirements screen. This screen simply ensures that the drive that you’ll be installing the SQL Server software onto has enough free space to hold the installation. The next screen, shown in Web Figure 1, lets you select the domain accounts that any new services will be running under.
The SQL Server service isn’t listed here because changing the account that it runs under isn’t supported. In this case, SQL Server Browser was configured to run under the domain account CORP\SQLServer. Because the Full Text Search service can run under a domain account and is configured as a clustered service in SQL Server 2008, it’s listed so that you can configure it to run under a domain account. Typically, you’d select the same account to run this service as the one that runs the SQL Server service, but that’s not required. After you’ve set the necessary usernames and passwords for your environment (the services listed on your screen might vary based on the services you have installed), click Next.
If you’ve chosen to install Full Text Search, the next screen you come to will ask you how you want to handle the full-text data. Your options are to import the data, rebuild the indexes, or reset the catalogs. If you choose to import the data, the full-text indexes will be imported as is. This process takes longer during the installation process because the full-text catalog must be loaded from the full-text files into the database itself. However, once the database is online, the full-text index will be fully populated. The downside to this option is that full-text indexes don’t use SQL Server 2008’s word breakers until the full-text index is rebuilt.
You can also choose to rebuild the catalog, which tells the SQL Server engine after the installation is done to do a complete rebuild of the full-text indexes. This process takes (depending on the size of the data being indexed by the full-text index) a lot of CPU and memory resources. However, the full-text data will be processed by SQL Server 2008’s word breakers. Although this is faster than importing the data during the installation process, if your tables are quite large, your full-text index could take a while to populate, which could result in incomplete search results when searches are run against the full-text feature of the database engine.
Your third option is to reset the catalogs, which tells the SQL Server engine to drop the old full-text database files and reset the catalogs. The metadata for the full-text catalogs and indexes is retained; however, the catalogs will be empty until you trigger a full rebuild manually once the upgrade has been completed. If you select this option, no results will be returned from the full-text engine until you trigger the full population of the data in the catalogs. After you’ve selected the way you want to process the full-text indexes, click Next.
The next screen is the standard error reporting and feature reporting screen. Microsoft recommends that you select both of the check boxes on this screen. If you select these check boxes, SQL Server will transmit error and usage data to Microsoft on a regular basis so that Microsoft can more quickly respond to problems with the project as well as market usage trends. However, this is optional and should be set per your company’s guidelines.
The next screen verifies that the system can handle the upgrade. Various checks are performed to ensure that the OS is capable of running SQL Server 2008 with the features that you selected. Note that these checks don’t check your database code to ensure that the database code will run on SQL Server 2008 without any problems. If there are any errors on this screen, you’ll need to resolve them before continuing with the installation.
The next screen shows you summary information about the cluster, as shown in Figure 4.
It shows both nodes of the cluster, that they’re currently both SQL Server 9.3.4035 (depending on the service pack and hotfix you have installed, this build number might vary), and which node is online. As I mentioned earlier, SQL Server will move the instance to another node in the cluster to minimize downtime.