ClickHouse tips and tricks / Thu, 05 Oct 2023 04:56:44 +0000 Thu, 05 Oct 2023 04:56:44 +0000 Jekyll v3.9.3 <p>How do you find out how large your ClickHouse tables are?</p> <p>The <code class="language-plaintext highlighter-rouge">system.parts</code> table in ClickHouse contains all information regarding table sizes and more.</p> <p>To find out the size of your tables, you can query for that information in the following manner:</p> <div class="language-sql highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="k">SELECT</span> <span class="k">table</span><span class="p">,</span> <span class="n">formatReadableSize</span><span class="p">(</span><span class="k">sum</span><span class="p">(</span><span class="n">bytes</span><span class="p">))</span> <span class="k">as</span> <span class="k">size</span><span class="p">,</span> <span class="k">min</span><span class="p">(</span><span class="n">min_date</span><span class="p">)</span> <span class="k">as</span> <span class="n">min_date</span><span class="p">,</span> <span class="k">max</span><span class="p">(</span><span class="n">max_date</span><span class="p">)</span> <span class="k">as</span> <span class="n">max_date</span> <span class="k">FROM</span> <span class="k">system</span><span class="p">.</span><span class="n">parts</span> <span class="k">WHERE</span> <span class="n">active</span> <span class="k">GROUP</span> <span class="k">BY</span> <span class="k">table</span><span... Wed, 04 Oct 2023 12:00:00 +0000 /how-to-query-table-sizes/ /how-to-query-table-sizes/ clickhouse operations howto clickhouse