title: SQL Server update trigger is not working
body: <p>There's a database table that has an update trigger. Whenever a column is updated, one of its columns is automatically calculated.</p>
  
  <p>I have tweaked the trigger and I'd like to run it on all of the rows again. In SQL Server Management Studio, if I choose "Edit Top 200 Rows" on my table and edit one of the rows, the update trigger works. But when I write a query like:</p>
  
  <pre><code>UPDATE MyTable
  SET SomeIrrelevantColumn = 0
  </code></pre>
  
  <p>the trigger doesn't work, the column that is supposed to be calculated by the trigger stays the same.</p>
  
  <p>How can I run the trigger manually on all the rows?</p>
  
  <p><strong>Edit:</strong> Here's the trigger:</p>
  
  <pre><code>USE [MY_DATABASE]
  GO
  /****** Object:  Trigger [dbo].[MY_TABLE_AUER]    Script Date: 04/24/2013 00:05:23 ******/
  SET ANSI_NULLS ON
  GO
  SET QUOTED_IDENTIFIER ON
  GO
  ALTER TRIGGER [dbo].[MY_TABLE_AUER] 
     ON  [dbo].[MY_TABLE] 
     AFTER UPDATE
  AS 
  DECLARE @UPD_COLUMN_A int,
          @INS_COLUMN_A int,
          @UPD_COLUMN_B int,
          @UPD_COLUMN_C varchar(255),
          @UPD_COLUMN_D varchar(255),
          @UPD_COLUMN_E int,
          @UPD_COLUMN_F datetime
  BEGIN
      -- SET NOCOUNT ON added to prevent extra result sets from
      -- interfering with SELECT statements.
      SET NOCOUNT ON;
      SELECT @UPD_COLUMN_A = _Column_A,
             @UPD_COLUMN_B =_Column_B,
             @UPD_COLUMN_C = COLUMN_C,
             @UPD_COLUMN_D = [Column_D]
        FROM DELETED;
      IF @UPD_COLUMN_D not like '%SomeString%'
      BEGIN
        SELECT @INS_COLUMN_A = _Column_A
          FROM INSERTED;
        IF @UPD_COLUMN_A != @INS_COLUMN_A
        BEGIN
          SELECT @UPD_COLUMN_E = MAX([_Column_B]),
                 @UPD_COLUMN_F = MAX([_Column_G])
            FROM MY_TABLE
           WHERE COLUMN_C = @UPD_COLUMN_C
             AND [Column_D] LIKE '%SomeString%';
          UPDATE MY_TABLE 
             SET COLUMN_E = @UPD_COLUMN_E,
                 COLUMN_F = @UPD_COLUMN_F
           WHERE [_Column_B] = @UPD_COLUMN_B;
          UPDATE MY_TABLE 
             SET COLUMN_H = @UPD_COLUMN_B
           WHERE [_Column_B] = @UPD_COLUMN_E; 
        END
      END
  END
  </code></pre>