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   <section id="system-tables">
 <h1>System Tables<a class="headerlink" href="#system-tables" title="Link to this heading">#</a></h1>
 <p>Paimon C++ supports reading system tables by appending a system table suffix to
 the data table path. For example, <code class="docutils literal notranslate"><span class="pre">/warehouse/db.db/orders$snapshots</span></code> reads
 the snapshots system table for <code class="docutils literal notranslate"><span class="pre">orders</span></code>.</p>
 <p>Branch-qualified paths are also supported. For example,
 <code class="docutils literal notranslate"><span class="pre">/warehouse/db.db/orders$branch_audit$files</span></code> reads the files system table from
 the <code class="docutils literal notranslate"><span class="pre">audit</span></code> branch.</p>
 <section id="read-optimized-system-table">
 <h2>Read-Optimized System Table<a class="headerlink" href="#read-optimized-system-table" title="Link to this heading">#</a></h2>
 <p>The read-optimized system table is addressed by the <code class="docutils literal notranslate"><span class="pre">$ro</span></code> suffix:</p>
 <div class="highlight-text notranslate"><div class="highlight"><pre><span></span>/warehouse/db.db/orders$ro
 </pre></div>
 </div>
 <p>For primary-key tables, <code class="docutils literal notranslate"><span class="pre">$ro</span></code> only plans data files from the highest LSM
 level, which is the level produced by full compaction. This avoids merging data
 from multiple LSM levels during query planning and reading. The tradeoff is that
 the result may lag behind the latest committed data until a full compaction
 publishes the newest records into the highest level.</p>
 <p>This stale view is not guaranteed to correspond to any single historical table
 snapshot. Full compaction may finish independently for different buckets. When
 <code class="docutils literal notranslate"><span class="pre">$ro</span></code> scans the latest snapshot, the selected highest-level files can
 therefore combine bucket states produced by full-compaction commits at different
 snapshot IDs.</p>
 <p>For primary-key tables, <code class="docutils literal notranslate"><span class="pre">$ro</span></code> also enables value-stats filtering, so file-level
 pruning of the reader predicate can be more aggressive than the base table.</p>
 <p>For append-only tables, <code class="docutils literal notranslate"><span class="pre">$ro</span></code> has the same read behavior as the base table,
 including streaming reads.</p>
 <section id="limitations">
 <h3>Limitations<a class="headerlink" href="#limitations" title="Link to this heading">#</a></h3>
 <ul class="simple">
 <li><p>Primary-key <code class="docutils literal notranslate"><span class="pre">$ro</span></code> scans are batch-only. Streaming scans are not supported.</p></li>
 <li><p>Freshness depends on full compaction frequency, and the result may not match
 any single historical snapshot across buckets.</p></li>
 <li><p>Primary-key tables in bucket-unaware mode are not supported by the current C++
 scan path.</p></li>
 </ul>
 </section>
 <section id="typical-usage">
 <h3>Typical Usage<a class="headerlink" href="#typical-usage" title="Link to this heading">#</a></h3>
 <p>Use <code class="docutils literal notranslate"><span class="pre">$ro</span></code> for OLAP or batch workloads that can tolerate stale results and
 prefer reading compacted files directly. Use the base table path when the query
 must see the latest committed data.</p>
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