title: Append a text to first column only using arrayformula in Google Sheets
body: <p>I have a query formula result range with n rows and 2 columns.</p>
  <p><a href="https://i.stack.imgur.com/l9U9h.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/l9U9h.png" alt="enter image description here" /></a></p>
  <p>I need to make it display as shown below</p>
  <p><a href="https://i.stack.imgur.com/6vUA8.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/6vUA8.png" alt="enter image description here" /></a></p>
  <p>Its prefixing text &quot;MWST (&quot; and suffixing &quot;%)&quot; to the first column</p>
  <p>I have tried with</p>
  <pre><code>=arrayformula(&quot;MWST (&quot; &amp; query(BuchungSystem!A2:AZ,&quot;Select SUM(M), N where Q = &quot;&amp; $B$10 &amp; &quot;GROUP BY L, N LABEL SUM(M) ''&quot;,-1)) 
  </code></pre>
  <p>but this gets prefix for second column too. I am getting this incorrect.</p>
  <p><a href="https://i.stack.imgur.com/mbKqv.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/mbKqv.png" alt="enter image description here" /></a></p>