[sql] How do I find the data directory for a SQL Server instance?

We have a few huge databases (20GB+) which mostly contain static lookup data. Because our application executes joins against tables in these databases, they have to be part of each developers local SQL Server (i.e. they can't be hosted on a central, shared database server).

We plan on copying a canonical set of the actual SQL Server database files (*.mdf and *.ldf) and attach them to each developer's local database.

What's the best way to find out the local SQL Server instance's data directory so we can copy the files to the right place? This will be done via an automated process, so I have to be able to find and use it from a build script.

SELECT DISTINCT dbo.GetDirectoryPath(filename) AS InstanceDataPaths
FROM sys.sysaltfiles WHERE filename like '%.mdf' and filename not like '%\MSSQL\Binn\%'

SELECT DISTINCT dbo.GetDirectoryPath(filename) AS InstanceLogPaths
FROM sys.sysaltfiles WHERE filename like '%.ldf' and filename not like '%\MSSQL\Binn\%'

You can download detail SQL script from how to find the data directory for a SQL Server instance

I stumbled across this solution in the documentation for the Create Database statement in the help for SQL Server:

SELECT SUBSTRING(physical_name, 1, CHARINDEX(N'master.mdf', LOWER(physical_name)) - 1)
                  FROM master.sys.master_files
                  WHERE database_id = 1 AND file_id = 1

i would have done a backup restore simply becuase its easier and support versioning. Reference data especially needs to be versioned in order to know when it started taking effect. A dettach attach wont give you that ability. Also with backups you can continue to provide updated copies without having to shut down the database.

Even though this is a very old thread, I feel like I need to contribute a simple solution. Any time that you know where in Management Studio a parameter is located that you want to access for any sort of automated script, the easiest way is to run a quick profiler trace on a standalone test system and capture what Management Studio is doing on the backend.

In this instance, assuming you are interested in finding the default data and log locations you can do the following:

SELECT
     SERVERPROPERTY('instancedefaultdatapath') AS [DefaultFile],
     SERVERPROPERTY('instancedefaultlogpath') AS [DefaultLog]

Small nitpick: there is no data folder, only a default data folder.

Anyway, to find it, assuming you want to install for the first default instance:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL.1\Setup\SQLDataRoot

If there's a named instance, MSSQL.1 becomes something like MSSQL10.INSTANCENAME.

Alex's answer is the right one, but for posterity here's another option: create a new empty database. If you use CREATE DATABASE without specifying a target dir you get... the default data / log directories. Easy.

Personally however I'd probably either:

• RESTORE the database to the developer's PC, rather than copy/attach (backups can be compressed, exposed on a UNC), or
• Use a linked server to avoid doing this in the first place (depends how much data goes over the join)

ps: 20gb is not huge, even in 2015. But it's all relative.

From the GUI: open your server properties, go to Database Settings, and see Database default locations.

Note that you can drop your database files wherever you like, though it seems cleaner to keep them in the default directory.

You will get default location if user database by this query:

declare @DataFileName nVarchar(500)

declare @LogFileName   nVarchar(500)


set @DataFileName = (select top 1 RTRIM(LTRIM(name)) FROM master.sys.master_files where database_id >4 AND file_id = 1)+'.mdf'
set @LogFileName =   (select top 1 RTRIM(LTRIM(name)) FROM master.sys.master_files where database_id >4 AND file_id = 2)+'.ldf'

select  
( SELECT top 1 SUBSTRING(physical_name, 1, CHARINDEX(@DataFileName, LOWER(physical_name)) - 1) 
FROM master.sys.master_files
WHERE database_id >4 AND file_id = 1) as 'Data File'
,

(SELECT top 1 SUBSTRING(physical_name, 1, CHARINDEX(@LogFileName, LOWER(physical_name)) - 1)
FROM master.sys.master_files
WHERE database_id >4 AND file_id = 2)  as 'Log File'

Keeping it simple:

use master
select DB.name, F.physical_name from sys.databases DB join sys.master_files F on DB.database_id=F.database_id

this will return all databases with associated files

As of Sql Server 2012, you can use the following query:

SELECT SERVERPROPERTY('INSTANCEDEFAULTDATAPATH') as [Default_data_path], SERVERPROPERTY('INSTANCEDEFAULTLOGPATH') as [Default_log_path];

(This was taken from a comment at http://technet.microsoft.com/en-us/library/ms174396.aspx, and tested.)

Various components of SQL Server (Data, Logs, SSAS, SSIS, etc) have a default directory. The setting for this can be found in the registry. Read more here:

http://technet.microsoft.com/en-us/library/ms143547%28SQL.90%29.aspx

So if you created a database using just CREATE DATABASE MyDatabaseName it would be created at the path specified in one of the settings above.

Now, if the admin / installer changed the default path, then the default path for the instance is stored in the registry at

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\[INSTANCENAME]\Setup

If you know the name of the instance then you can query the registry. This example is SQL 2008 specific - let me know if you need the SQL2005 path as well.

DECLARE @regvalue varchar(100)

EXEC master.dbo.xp_regread @rootkey='HKEY_LOCAL_MACHINE',
        @key='SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL10.MSSQLServer\Setup',
        @value_name='SQLDataRoot',
        @value=@regvalue OUTPUT,
        @output = 'no_output'

SELECT @regvalue as DataAndLogFilePath

Each database can be created overriding the server setting in a it's own location when you issue the CREATE DATABASE DBName statement with the appropriate parameters. You can find that out by executing sp_helpdb

exec sp_helpdb 'DBName'

For the current database you can just use:

select physical_name fromsys.database_files;

to specify another database e.g. 'Model', use sys.master_files

select physical_name from sys.master_files where database_id = DB_ID(N'Model');

Expanding on "splattered bits" answer, here is a complete script that does it:

@ECHO off
SETLOCAL ENABLEDELAYEDEXPANSION

SET _baseDirQuery=SELECT SUBSTRING(physical_name, 1, CHARINDEX(N'master.mdf', LOWER(physical_name)) - 1) ^
 FROM master.sys.master_files WHERE database_id = 1 AND file_id = 1;
ECHO.
SQLCMD.EXE -b -E -S localhost -d master -Q "%_baseDirQuery%" -W >data_dir.tmp
IF ERRORLEVEL 1 ECHO Error with automatically determining SQL data directory by querying your server&ECHO using Windows authentication.
CALL :getBaseDir data_dir.tmp _baseDir

IF "%_baseDir:~-1%"=="\" SET "_baseDir=%_baseDir:~0,-1%"
DEL /Q data_dir.tmp
echo DataDir: %_baseDir%

GOTO :END
::---------------------------------------------
:: Functions 
::---------------------------------------------

:simplePrompt 1-question 2-Return-var 3-default-Val
SET input=%~3
IF "%~3" NEQ "" (
  :askAgain
  SET /p "input=%~1 [%~3]:"
  IF "!input!" EQU "" (
    GOTO :askAgain
  ) 
) else (
  SET /p "input=%~1 [null]: "
)   
SET "%~2=%input%"
EXIT /B 0

:getBaseDir fileName var
FOR /F "tokens=*" %%i IN (%~1) DO (
  SET "_line=%%i"
  IF "!_line:~0,2!" == "c:" (
    SET "_baseDir=!_line!"
    EXIT /B 0
  )
)
EXIT /B 1

:END
PAUSE

You can find default Data and Log locations for the current SQL Server instance by using the following T-SQL:

DECLARE @defaultDataLocation nvarchar(4000)
DECLARE @defaultLogLocation nvarchar(4000)

EXEC master.dbo.xp_instance_regread
    N'HKEY_LOCAL_MACHINE',
    N'Software\Microsoft\MSSQLServer\MSSQLServer',
    N'DefaultData', 
    @defaultDataLocation OUTPUT

EXEC master.dbo.xp_instance_regread
    N'HKEY_LOCAL_MACHINE',
    N'Software\Microsoft\MSSQLServer\MSSQLServer',
    N'DefaultLog', 
    @defaultLogLocation OUTPUT

SELECT @defaultDataLocation AS 'Default Data Location',
       @defaultLogLocation AS 'Default Log Location'