title: How to remove duplicate values from a multi-dimensional array in PHP
body: <p>How can I remove duplicate values from a multi-dimensional array in PHP?</p>
  
  <p>Example array:</p>
  
  <pre><code>Array
  (
      [0] =&gt; Array
      (
          [0] =&gt; abc
          [1] =&gt; def
      )
  
      [1] =&gt; Array
      (
          [0] =&gt; ghi
          [1] =&gt; jkl
      )
  
      [2] =&gt; Array
      (
          [0] =&gt; mno
          [1] =&gt; pql
      )
  
      [3] =&gt; Array
      (
          [0] =&gt; abc
          [1] =&gt; def
      )
  
      [4] =&gt; Array
      (
          [0] =&gt; ghi
          [1] =&gt; jkl
      )
  
      [5] =&gt; Array
      (
          [0] =&gt; mno
          [1] =&gt; pql
      )
  
  )
  </code></pre>