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I learned how to use the Levenshtein functions in PostgreSQL
The thing is that there is a limit of 255 characters for these functions in PostgreSQL so you need to truncate the strings before comparing
Also, the trgm functions I’ve used before are case insensitive, but Levenshtein is not, so you need to make sure to lower case both strings first
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I learned how to use the Levenshtein functions in PostgreSQL
The thing is that there is a limit of 255 characters for these functions in PostgreSQL so you need to truncate the strings before comparing
Also, the trgm functions I’ve used before are case insensitive, but Levenshtein is not, so you need to make sure to lower case both strings first
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<h2 id="2022-07-02">2022-07-02</h2>
<ul>
<li>I learned how to use the Levenshtein functions in PostgreSQL
<ul>
<li>The thing is that there is a limit of 255 characters for these functions in PostgreSQL so you need to truncate the strings before comparing</li>
<li>Also, the trgm functions I’ve used before are case insensitive, but Levenshtein is not, so you need to make sure to lower case both strings first</li>
</ul>
</li>
</ul>
<ul>
<li>A working query checking for duplicates in the recent AfricaRice items is:</li>
</ul>
<div class="highlight"><pre tabindex="0" style="color:#f8f8f2;background-color:#272822;-moz-tab-size:4;-o-tab-size:4;tab-size:4;"><code class="language-console" data-lang="console"><span style="display:flex;"><span>localhost/dspace= ☘ SELECT text_value FROM metadatavalue WHERE dspace_object_id IN (SELECT uuid FROM item) AND metadata_field_id=64 AND levenshtein_less_equal(LOWER('International Trade and Exotic Pests: The Risks for Biodiversity and African Economies'), LEFT(LOWER(text_value), 255), 3) <= 3;
</span></span><span style="display:flex;"><span> text_value
</span></span><span style="display:flex;"><span>────────────────────────────────────────────────────────────────────────────────────────
</span></span><span style="display:flex;"><span> International trade and exotic pests: the risks for biodiversity and African economies
</span></span><span style="display:flex;"><span>(1 row)
</span></span><span style="display:flex;"><span><span style="color:#960050;background-color:#1e0010">
</span></span></span><span style="display:flex;"><span><span style="color:#960050;background-color:#1e0010"></span>Time: 399.751 ms
</span></span></code></pre></div><ul>
<li>There is a great <a href="https://www.crunchydata.com/blog/fuzzy-name-matching-in-postgresql">blog post discussing Soundex with Levenshtein</a> and creating indexes to make them faster</li>
<li>I want to do some proper checks of accuracy and speed against my trigram method</li>
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<h2 id="2022-07-03">2022-07-03</h2>
<ul>
<li>Start a harvest on AReS</li>
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