title: Oracle: Update a datarow by adding to existing value
body: <p>I have a big table in my database(Oracle 11g) where I want to update a column of the table where I have specific numbers in it.
  I want to update it with setting a <code>prefix</code> infront of every value of this column.</p>
  
  <p><strong>Example</strong> (SpecificNumber is <code>int</code> and the PK, Value1 is <code>Varchar2</code> and so is the last column):</p>
  
  <p>Actual data:</p>
  
  <pre><code>    [SpecificNumber] [Value1] [column2gettingupdated]
  [1]  123456789        Test     text    
  [2]  123456789102     sth      text2    
  [3]  12233            text     test3
  </code></pre>
  
  <p>Future data(after my sql):</p>
  
  <pre><code>    [SpecificNumber] [Value1] [column2gettingupdated]
  [1]  123456789        Test     PREFIX-text    
  [2]  123456789102     sth      PREFIX-text2    
  [3]  12233            text     PREFIX-test3
  </code></pre>
  
  <p>So what I thought about:</p>
  
  <pre><code>Update table
  set column2gettingupdated=("prefix"+
      (select column2gettingupdated from table where SpecificNumber = '12233')
  )
  where SpecificNumber = '12233';
  </code></pre>
  
  <p>But that gives me an <code>ORA-00904: "p": invalid identifier</code> error.</p>
  
  <p>And if I try this:</p>
  
  <pre><code>Update table
  set column2gettingupdated=("prefix"+
      (select column2gettingupdated from table where SpecificNumber = '12233')
  )
  where SpecificNumber = '12233';
  </code></pre>
  
  <p>I get an <code>ORA-01722: invalid number</code> error.</p>
  
  <p>Is this even possible ? Already thanks for your help!</p>