title: SQL update query using joins
body: <p>I have to update a field with a value which is returned by a join of 3 tables.</p>
  
  <p>Example: </p>
  
  <pre><code>select
      im.itemid
      ,im.sku as iSku
      ,gm.SKU as GSKU
      ,mm.ManufacturerId as ManuId
      ,mm.ManufacturerName
      ,im.mf_item_number
      ,mm.ManufacturerID
  from 
      item_master im, group_master gm, Manufacturer_Master mm 
  where
      im.mf_item_number like 'STA%'
      and im.sku=gm.sku
      and gm.ManufacturerID = mm.ManufacturerID
      and gm.manufacturerID=34
  </code></pre>
  
  <p>I want to update the <code>mf_item_number</code> field values of table <code>item_master</code> with some other value which is joined in the above condition.</p>
  
  <p>How can I do this in MS SQL Server?</p>