Filter duplicate students via T-SQL

• kevin_nikolai

  SSCarpal Tunnel

  Points: 4343

  More actions

  April 19, 2013 at 6:56 am

  #273177

  /*

  I need to filter for duplicate students:

  ---------------------------------------

  For same student, if one or both instance/s of IDNo is null then do the following:

  1.

  if both instances of Tel3 are identical for same Student (Alison), if they are

  use it to populate field Sort with the value.

  2.

  if both instances of Tel3 are not identical for same Student (Carmen), check if both instances of Tel2 are identical for same Student, if they are use it to populate field Sort with the value.

  3.

  if both instances of Tel3 and Tel2 are not identical for same Student (Amber), check if an instance of Tel3 & Tel2 are identical for same Student, if they are use it to populate field Sort with the value.

  */

  SELECT 'Alison' as Student, NULL as IDNo, '1111' as Tel3, '1111' as Tel1, NULL as Sort UNION ALL

  SELECT 'Alison' as Student, '80405088' as IDNo, '1111' as Tel3, '1111' as Tel1, NULL as Sort UNION ALL

  SELECT 'Amber' as Student, NULL as IDNo, '5555' as Tel3, '6666' as Tel1, NULL as Sort UNION ALL

  SELECT 'Amber' as Student, NULL as IDNo, '7777' as Tel3, '7777' as Tel1, NULL as Sort UNION ALL

  SELECT 'Carmen' as Student, NULL as IDNo, '8888' as Tel3, '8888' as Tel1, NULL as Sort UNION ALL

  SELECT 'Carmen' as Student, '20083085' as IDNo, '9999' as Tel3, '8888' as Tel1, NULL as Sort

• Sean Lange

  SSC Guru

  Points: 286590

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  April 19, 2013 at 7:51 am

  #1608225

  duplicate post. direct replies here. http://www.sqlservercentral.com/Forums/Topic1444358-392-1.aspx

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