Migration Type: Delta Migrations

Migration Type: Delta Migrations

A "Delta" migration is necessary when you migrate some data now and some data later.

To do a Delta migration, please follow the steps below after you have complete the initial backup and restore.

1.  Create the "Phase 2" Backup

Using Universal Migrator, perform a new backup of the source system.

2.  Copy Result_Ids from "Phase 1" to "Phase 2"

Replace the Database Names
In the following script, replace PHASE1_DB and PHASE2_DB with the names of the respective database names.

If you want to copy the Result_Ids for all tables, simply use the query below.


  2. use [PHASE1_DB]

  4. exec sp_MSforeachtable '


  7. UPDATE

  9.     [PHASE2_DB].?
  10. SET
  11.     Comment = Phase1.Comment,
  12.     Batch_Number = Phase1.Batch_Number,
  13.     Batch_Group = Phase1.Batch_Group,
  14.     Status_ReferenceCode = Phase1.Status_ReferenceCode,
  15.     Status_Description = Phase1.Status_Description,
  16.     Status_Date_From = Phase1.Status_Date_From,
  17.     Status_Date_Till = Phase1.Status_Date_Till,
  18.     Result_Id = Phase1.Result_Id,
  19.     Result_ReferenceCode = Phase1.Result_ReferenceCode
  20. FROM 
  21.     [PHASE1_DB].? Phase1,
  22.     [PHASE2_DB].? Phase2
  23. WHERE 1=1
  24.     and Phase1.Id = Phase2.Id
  25.     and Phase2.Result_Id = ''''
  26. '

 

Or if you want to copy the Result_Ids for one specific table, use the query below:

  1. USE [PHASE2_DB]

  3. UPDATE
  4.     [PHASE2_DB].dbo.__M_Matters
  5. SET
  6.     Comment = Phase1.Comment,
  7.     Batch_Number = Phase1.Batch_Number,
  8.     Batch_Group = Phase1.Batch_Group,
  9.     Status_ReferenceCode = Phase1.Status_ReferenceCode,
  10.     Status_Description = Phase1.Status_Description,
  11.     Status_Date_From = Phase1.Status_Date_From,
  12.     Status_Date_Till = Phase1.Status_Date_Till,
  13.     Result_Id = Phase1.Result_Id,
  14.     Result_ReferenceCode = Phase1.Result_ReferenceCode

  16. FROM
  17.     [PHASE1_DB].dbo.__M_Matters Phase1,
  18.     [PHASE2_DB].dbo.__M_Matters Phase2
  19. WHERE 1=1
  20.     and Phase1.Id = Phase2.Id 
  21.     and Phase2.Result_Id = ''

3.  Restore / Tweak using the "Phase 2" Backup

After the above script runs, the "Phase 2" database will now have Result_Ids in it.  This will allow you to safely restore or tweak records.

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