need to move data from one field to another, within the same table

Question

I want to move all data from field_id_41 into field_id_380, where weblog_id = 191

Those two fields belong to the same table: exp_weblog_data

I do not want to run anything without asking here, I started to put this together:

UPDATE 
  exp_weblog_data 
SET 
  field_id_380 = (SELECT field_id_41 FROM exp_weblog_data 
  WHERE (field_id_41 != '' and weblog_id = 191)) 
WHERE 
  weblog_id = 191

Answer 1

Really no need for the subquery. You can just take the value for the other column in the same row, and set it in the first column:

UPDATE 
  exp_weblog_data 
SET 
  field_id_380 =field_id_41 
WHERE 
  weblog_id = 191
AND 
  field_id_41 != ''

Answer 2

maybe like this:

UPDATE 
  exp_weblog_data 
SET 
  field_id_380 =field_id_41,   field_id_41 = ''
WHERE 
  weblog_id = 191
AND 
  field_id_41 != ''