title: Exact matching regex replace
body: <p>I need to replace <code>@TableName1</code> to <code>test</code> using Regex in the following string:</p>
  
  <pre><code>@TableName1, @TableName11
  pk_@TableName1_1, @TableName1_12
  @TableName2
  </code></pre>
  
  <p>to look like this:</p>
  
  <pre><code>test, @TableName11
  pk_test_1, test_12
  @TableName2
  </code></pre>
  
  <p>I tried to use <code>\B@TableName1\b</code> but when I do this the <code>pk_@TableName1_1</code> is not replaced.</p>
  
  <p>What should I do in such scenario?</p>