Microsoft Official 32 version of the trial version. The file name is Sqlfull_x86_enu.exe. The file size is around 1.30G. Because there are only 32-bit versions, the 3G is smaller than SQL Server 2008.
Http://www.microsoft.com/sqlserver/2008/en/us/R2Downloads.aspx
After the download is complete, uninstall the original SQL Server SP2, and the results run for two hours, because the installation mechanism of SQL Server 2008 is based on the framework rewrite, which is characterized by a very time-consuming (my little laptop configuration is still possible.) ^_^). But you don't need the original ISO or the hidden MSI file (you don't have to worry if you accidentally delete the installation files manually). This is why most of the time, the SQL Server 2008 installation log file Setup.log will have a 1G size. Because the installation process is too large.
Anyway After the uninstallation is complete, restart the machine. Note that because SQL Server 2008 was previously installed, some components, such as the. NET Framework SP1, do not have to be installed.
See also: Installation of sql2008 Enterprise (English version) illustration
The following is the SQL Server R2 installation process, in fact, the installation of SQL Server 2008 is very similar, just a little bit sorry to the audience, hereby apologize!
RELATED links: SQL Server R2 Installation Quick Start
"Reprint-Invitation Month Studio" SQL Server 2008