I have a huge table with many columns and I know that this columns sometimes takes some specific value \'MyValue\'. How can I select all the rows in that one specific table
You can concatenate all columns with + and then perform a LIKE search:
+
LIKE
SELECT * FROM data WHERE col1 + '#' + col2 + '#' + col3 like '%test%'
Adding a separator (I use #) between the columns ensures you won't get false positives from the concatenation, e.g. if col2 = 'te' and col3 = 'st'
#
SQL Fiddle