Answers.Body: <p>Its possible to update the contact using the same csv if you have unique identifier for each row and the same is stored in CiviCRM database either as CiviCRM Contact ID or contact external identifier for each contact. </p>
  
  <p>During import select 'Update' for duplicate contacts and then in mapping make sure you use either external identifier or contact id. If this 2 fields are used during import than the contact's are directly updated into the system without performing any dedupe checks like firstname-lastname or email which is again unique way of avoiding duplicate contact into system. </p>
  
  <p><a href="https://i.sstatic.net/CzrHL.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/CzrHL.png" alt="enter image description here"></a></p>
  
  <p>If you have stored <code>custom unique key field for each record</code> in contact's custom field then probably you will need to run a query which will update the external identifier for a contact and make it easy for you to import again using same sheet.</p>
  
  <pre><code>The sql would be something like:
  
  UPDATE civicrm_contact cc
  INNER JOIN civicrm_value_custom_table cv ON cv.entity_id = cc.id
  SET cc.external_identifier = cv.custom_unique_id_field;
  </code></pre>
  
  <blockquote>
    <p><strong>Note:</strong> Backup your database before performing contact import or running
    any  Insert/Update/Delete sql.</p>
  </blockquote>
  
  <p>HTH </p>
  
  <p>Pradeep</p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2018-04-27T15:01:35.717Z
Answers.LastActivityDate: 2018-04-27T15:01:35.717Z
Answers.UserDisplayName: Pradeep Nayak
Answers.Body: <p>Simple.
  - Use the same sheet.
  - You have an option in the wizard to determine how to handle duplicates. Choose 'fill'.
  - Only match the unique ID field to 'external id' and the missing collumn and hit import.</p>
  
  <p>Always a good idea to backup your database before doing an import.</p>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2018-04-27T14:50:18.087Z
Answers.LastActivityDate: 2018-04-27T14:50:18.087Z
Answers.UserDisplayName: Yossi
Body: <p>Hopefully the title is self explanitory. I have uploaded contact data but forgot to include one field. I now need to update the relevant field on all the records with with the data held on the csv. I did upload a custom unique key field for each record when originally uploaded the data.</p>
  
  <p>Any help would be appreciated.</p>
  
  <p>John</p>
  
Tags: <wordpress>
Title: Updating fields in existing records from csv file
ThreadText: # Updating fields in existing records from csv file
  
  (Asked by: username_0 on 2018-04-27)
  
  Hopefully the title is self explanitory. I have uploaded contact data but forgot to include one field. I now need to update the relevant field on all the records with with the data held on the csv. I did upload a custom unique key field for each record when originally uploaded the data.
  
  Any help would be appreciated.
  
  John
  
  **Tags:** wordpress
  
  
  ---
  
  ## 2 answers
  
  ### Answer by username_1 on 2018-04-27. Score: 1
  
  Its possible to update the contact using the same csv if you have unique identifier for each row and the same is stored in CiviCRM database either as CiviCRM Contact ID or contact external identifier for each contact. 
  During import select 'Update' for duplicate contacts and then in mapping make sure you use either external identifier or contact id. If this 2 fields are used during import than the contact's are directly updated into the system without performing any dedupe checks like firstname-lastname or email which is again unique way of avoiding duplicate contact into system. 
  
  If you have stored custom unique key field for each record in contact's custom field then probably you will need to run a query which will update the external identifier for a contact and make it easy for you to import again using same sheet.
  The sql would be something like:
  
  UPDATE civicrm_contact cc
  INNER JOIN civicrm_value_custom_table cv ON cv.entity_id = cc.id
  SET cc.external_identifier = cv.custom_unique_id_field;
  
  
  Note: Backup your database before performing contact import or running
    any  Insert/Update/Delete sql.
  
  HTH 
  Pradeep
  
  
  ---
  
  ### Answer by username_2 on 2018-04-27. Score: 0
  
  Simple.
  - Use the same sheet.
  - You have an option in the wizard to determine how to handle duplicates. Choose 'fill'.
  - Only match the unique ID field to 'external id' and the missing collumn and hit import.
  
  Always a good idea to backup your database before doing an import.
  
  
  ---
  
  