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Cognitive Sciences Meta

Q&A about the site for practitioners, researchers, and students in cognitive science, psychology, neuroscience, and psychiatry

-- Create cursor for list of sites
DECLARE sites CURSOR FOR
  SELECT name
  FROM sys.databases
  WHERE name NOT IN ('master', 'tempdb', 'model', 'msdb', 'Data.StackExchange')
-- And declare some variables
DECLARE @sitedbname AS nvarchar(max)
DECLARE @sitehostname AS nvarchar(max)
DECLARE @ispersitemeta AS bit

DECLARE @query AS nvarchar(max)
CREATE TABLE #out (
  Site nvarchar(max) NOT NULL,
  -- ↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓
  -- COLUMN NAMES WANT TO ADD SHOULD GO HERE   
  [User Count] int NOT NULL
  -- ↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑
)
-- These variables are for the SPOOKY HOSTNAME GENERATION CODE
DECLARE @spooky_string AS nvarchar(max)
DECLARE @spooky_delimiter AS char(1) = '.'
DECLARE @spooky_xml AS xml
DECLARE @spooky_result AS nvarchar(max)

-- Step through cursor
OPEN sites
FETCH NEXT FROM sites INTO @sitedbname
WHILE @@FETCH_STATUS = 0
BEGIN
  -----------------------------------------------------------------------------
  -- BEGIN SPOOKY HOSTNAME GENERATION CODE ------------------------------------
  -- adapted from <http://data.stackexchange.com/stackoverflow/query/256747/> -
  -----------------------------------------------------------------------------
  SET @spooky_string = @sitedbname
  SET @spooky_xml = CAST(('<X>' + REPLACE(@spooky_string, @spooky_delimiter, '</X><X>') + '</X>') AS xml)
  SET @spooky_result = ''

  SELECT
    C.value('.', 'nvarchar(max)') AS [Piece],
    C.value('for $i in . return count(../*[. << $i]) + 1', 'int') AS [Index]
  INTO #spooky_pieces
  FROM @spooky_xml.nodes('X') AS X(C)

  SELECT @spooky_result = COALESCE(@spooky_result + '.', '') + [Piece]
  FROM #spooky_pieces
  ORDER BY [Index] DESC

  DROP TABLE #spooky_pieces

  SET @sitehostname = 'http://' + RIGHT(@spooky_result, LEN(@spooky_result)-1) + '.com'
  SET @ispersitemeta = (CASE WHEN @sitedbname LIKE '%Meta%' AND @sitedbname != 'StackExchange.Meta' THEN 1 ELSE 0 END)

  ----------------------------------------
  -- HERE COME THE SPOOKY SPECIAL CASES --
  ----------------------------------------
  -- Meta MathOverflow doesn't have a redirect; see <http://meta.stackexchange.com/q/215071/224428>
  IF @sitedbname = 'StackExchange.Mathoverflow.Meta' SET @sitehostname = 'http://Meta.MathOverflow.net'
  -- For some reason probably involving the AVP/Audio/Video/Sound hullabaloo, there is 
  -- still a StackExchange.Audio DB that's getting updated. http://audio.stackexchange.com/
  -- no longer exists, so we use Video.SE for the hostname instead.
  IF @sitedbname = 'StackExchange.Audio' SET @sitehostname = 'http://Video.StackExchange.com'
  -----------------------------------------------------------------------------
  -- END SPOOKY HOSTNAME GENERATION CODE --------------------------------------
  -----------------------------------------------------------------------------

  -- ↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓
  -- CODE YOU WANT TO ADD SHOULD GO HERE
  -- for example,
  SET @query = '
    USE [' + @sitedbname + ']

    INSERT INTO #out
    SELECT
      ''' + @sitehostname + '|' + @sitedbname + ''' AS [Site],
      (Select Count(*) From Users) As [User Count]
    '
  EXEC sp_executesql @query
  -- ↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑

  FETCH NEXT FROM sites INTO @sitedbname
END
CLOSE sites
DEALLOCATE sites

-- Reap results (also optional)
SELECT
  *
FROM
  #out

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