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    <p>Paul told you about <a href="https://www.postgresql.org/docs/9.5/static/fuzzystrmatch.html#AEN169796" rel="nofollow noreferrer"><code>levenshtein()</code></a>. That's a very useful tool, but it's also very slow with big tables. It has to calculate the levenshtein-distance from the search term for every single row, that's expensive. </p> <p>First off, <em>if</em> your requirements are as simple as the example indicates, you can still use <code>LIKE</code>. Just replace any <code>-</code> in your search term with <code>%</code> to create the <code>WHERE</code> clause</p> <pre><code>WHERE code LIKE "%AB%123%lHdfj%" </code></pre> <p>instead of </p> <pre><code>WHERE code LIKE "%AB-123-lHdfj%" </code></pre> <p>If your real problem is <strong>more complex</strong> and you need something faster then - depending on your requirements - there are several options.</p> <ul> <li><p>There is <a href="http://www.postgresql.org/docs/current/interactive/textsearch.html" rel="nofollow noreferrer">full text search</a>, of course. But this may be an overkill in your case.</p></li> <li><p>A more likely candidate is <a href="http://www.postgresql.org/docs/current/interactive/pgtrgm.html" rel="nofollow noreferrer">pg_trgm</a>. Note that you can combine that with <code>LIKE</code> in PostgreSQL 9.1. See this <a href="http://www.depesz.com/index.php/2011/02/19/waiting-for-9-1-faster-likeilike/" rel="nofollow noreferrer">blog post by Depesz</a>.<br> Also very interesting in this context: the <code>similarity()</code> function or <code>%</code> operator of that module. More:</p> <ul> <li><a href="https://stackoverflow.com/questions/1566717/postgresql-like-query-performance-variations/13452528#13452528">PostgreSQL LIKE query performance variations</a></li> </ul></li> <li><p>Last but not least you can implement a hand-knit solution with a function to <strong>normalize</strong> the strings to be searched. For instance, you could transform <code>AB1-23-lHdfj</code> -> <code>ab123lhdfj</code>, save it in an additional column and search it with search terms that have been transformed the same way. </p> <p>Or use an <a href="http://www.postgresql.org/docs/current/interactive/indexes-expressional.html" rel="nofollow noreferrer">index on an expression</a> instead of the redundant column. (Involved functions must be <code>IMMUTABLE</code>.) And possibly combine that with <code>pg_tgrm</code> from above.</p></li> </ul> <p>Overview of pattern-matching techniques:</p> <ul> <li><a href="https://dba.stackexchange.com/questions/10694/pattern-matching-with-like-similar-to-or-regular-expressions-in-postgresql/10696#10696">Pattern matching with LIKE, SIMILAR TO or regular expressions in PostgreSQL</a></li> </ul>
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    1. POHow to create simple fuzzy search with Postgresql only?
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