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Updating column in SQL with Blank Value

If I need to replace all mentions of "TOTA" in a column with nothing would I use the following concept? It seems simple but all the tutorials that I find are not in plain enough English for someone who picked up SQL last week.

Update Tablename 
set indcode =case when indcode in('TOTA', then 'blank' else 'leave it alone' End);

You should set to null for assign blank value

Update Tablename 
 set indcode = NULL
 where indcode ='TOTA';

and use where for filter the row to update

if you need a set of value for filter you can use a IN clause eg

 Update Tablename 
 set indcode = NULL
 where indcode in ('TOTA', '0', '000000');

or for complex case you can use case when ..

 Update Tablename 
 set indcode = case when 'TOTA' then NULL 
                    when '0' then '000000'
                    else indcode 
                    END

You were missing a equal sign and a closing parentheses, and as written you would have updated it to the string blank, not an empty string, and finally, you need to decide if you want it to be updated to an empty (zero-length) string, or to the built-in database value called null, which represents, in all relational databases, that the value is not known or is unspecified (as opposed to explicitly being an empty or zero-length string.)

To update to an empty (zero-Length) string, write'

    Update Tablename 
      set indcode = case when indcode = 'TOTA' then '' 
                         else indcode end;

but you really don't need to update the ones to be left alone, so just add a filter (a Where clause) with that predicate expression

    Update Tablename 
      set indcode = ''
    Where indcode = 'TOTA' 

If you really want to update it to Null, and not to an empty string, then first check and make sure that the column indCode is set to allow nulls, and write:

    Update Tablename 
      set indcode = Null
    Where indcode = 'TOTA'  

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