擅长:python、mysql、java
<p>为此,可以使用<code>DENSE_RANK()</code>窗口函数:</p>
<pre class="lang-sql prettyprint-override"><code>select dataset.*, DENSE_RANK() OVER (ORDER BY email)
from dataset
order by sent;
</code></pre>
<p>这将产生如下结果(使用<a href="https://stackoverflow.com/a/66843476/466862">Mikhail Berlyant's example data</a>作为起点):</p>
<div class="s-table-container">
^{tb1}$
</div>