SQL Server express silent installation

SQL server setup supports silent installation options but it may be inconvenient to distribute this installation. One simple solution to this is to create your own installer as self extracting archive that embeds SQL server installation. There are different programs that support this functionality, I used 7-zip because it is open source. So here is an example of batch file that creates silent installation of SQL server 2014 express, it's pretty much the same for all older versions. Assumption is that downloaded SQLEXPR_x64_ENU.exe is located in the same folder as batch file. As a result it creates SQLServerExpress2014x64.exe which can be run to install SQL server.

set InstallName=SQLServerExpress2014x64.exe
set ArchiveName=SQLEXPR_x64_ENU.7z
if exist %InstallName% del /Q %InstallName%
if exist %ArchiveName% del /Q %ArchiveName%
"%PROGRAMFILES%\7-zip\7z.exe" a -t7z -r0 %ArchiveName% SQLEXPR_x64_ENU.exe

@echo ;!@Install@!UTF-8! >config.txt
@echo Title="SQL Server Express version 2014 64-bit">>config.txt
@echo BeginPrompt="Do you want to install SQL Server Express version 2014 64-bit?">>config.txt
:: here you can change options for SQL server installation, full list of options is here http://msdn.microsoft.com/en-us/library/ms144259.aspx
@echo RunProgram="SQLEXPR_x64_ENU.exe /q /ACTION=Install /SECURITYMODE=SQL /TCPENABLED=1 /INSTANCENAME=MSSQLSERVER /IACCEPTSQLSERVERLICENSETERMS /SAPWD=gfhjkm856 /ADDCURRENTUSERASSQLADMIN=True /SQLSVCACCOUNT=\"NT AUTHORITY\\Network Service\"">>config.txt
@echo ;!@InstallEnd@!>>config.txt

::SFX module can be downloaded from here http://downloads.sourceforge.net/sevenzip/7z920_extra.7z
copy /b "%ProgramFiles%\7-Zip\Extra\7zS.sfx" + config.txt + %ArchiveName% %InstallName%
if exist %ArchiveName% del /Q %ArchiveName%
if exist config.txt del /Q config.txt

One problem with this approach is that installer window is hidden so you can't see when it's finished, the only way to check for it is to see %temp%\SqlSetup.log file. You will also need to check this file to see if installation was successful, in this case exit code will be 0.