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    <blockquote> <p>To answer your question <strong>there is no difference between LEFT JOIN and LEFT OUTER JOIN, they are exactly same</strong> that said...</p> </blockquote> <h2>At the top level there are mainly 3 types of joins:</h2> <ol> <li>INNER</li> <li>OUTER</li> <li>CROSS</li> </ol> <hr> <ol> <li><p><strong>INNER JOIN</strong> - fetches data if present in both the tables.</p></li> <li><p><strong>OUTER JOIN</strong> are of <strong>3</strong> types:</p> <ol> <li><code>LEFT OUTER JOIN</code> - fetches data if present in the left table.</li> <li><code>RIGHT OUTER JOIN</code> - fetches data if present in the right table.</li> <li><code>FULL OUTER JOIN</code> - fetches data if present in either of the two tables.</li> </ol></li> <li><p><strong>CROSS JOIN</strong>, as the name suggests, does <code>[n X m]</code> that joins everything to everything.<br> Similar to scenario where we simply lists the tables for joining (in the <code>FROM</code> clause of the <code>SELECT</code> statement), using commas to separate them.</p></li> </ol> <hr> <p><strong>Points to be noted:</strong></p> <ul> <li>If you just mention <code>JOIN</code> then by default it is a <code>INNER JOIN</code>.</li> <li>An <code>OUTER</code> join has to be <code>LEFT</code> | <code>RIGHT</code> | <code>FULL</code> you can not simply say <code>OUTER JOIN</code>.</li> <li>You can drop <code>OUTER</code> keyword and just say <code>LEFT JOIN</code> or <code>RIGHT JOIN</code> or <code>FULL JOIN</code>.</li> </ul> <hr> <p>For those who want to visualise these in a better way, please go to this link: <a href="http://www.codinghorror.com/blog/2007/10/a-visual-explanation-of-sql-joins.html" rel="noreferrer">A Visual Explanation of SQL Joins</a></p>
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    1. POLEFT JOIN vs. LEFT OUTER JOIN in SQL Server
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    1. COVery good answer. It will be clearer if you say "LEFT OUTER JOIN - fetches all data from the left table with matching data from right, if preset." for 2.1 (and similar change for 2.2)
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    2. COAlso you can do cross join by simply 'select * from TableA,TableB'
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