Dynamically changing an order number to end in _ERR
It's going to be a different concatenation operator depending on the RDMS you're using. For instance:


Oracle uses ||
SQL Server uses +
MySQL uses concat


...but everything else looks like:

UPDATE table1 SET order = order ||'_ERR' WHERE [your condition]


Since the question is tagged for SQL Server, the applicable syntax is:

UPDATE table1 SET order = order +'_ERR' WHERE [your condition]