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copied!<ul> <li><p>In <code>SQL Server 2008</code> (and in <code>Oracle 10g</code>): <a href="http://technet.microsoft.com/en-us/library/bb510625.aspx" rel="nofollow noreferrer"><code>MERGE</code></a>.</p> <p>A single command to <code>INSERT / UPDATE / DELETE</code> into a table from a row source.</p></li> <li><p>To generate a list of numbers from <code>1</code> to <code>31</code> (say, for a calendary):</p> <pre><code>WITH cal AS ( SELECT 1 AS day UNION ALL SELECT day + 1 FROM cal WHERE day <= 30 ) </code></pre></li> <li><p>A single-column index with <code>DESC</code> clause in a clustered table can be used for sorting on <code>column DESC, cluster_key ASC</code>:</p> <pre><code>CREATE INDEX ix_column_desc ON mytable (column DESC) SELECT TOP 10 * FROM mytable ORDER BY column DESC, pk -- Uses the index SELECT TOP 10 * FROM mytable ORDER BY column, pk -- Doesn't use the index </code></pre></li> <li><p><code>CROSS APPLY</code> and <code>OUTER APPLY</code>: enables to join rowsources which depend on the values of the tables being joined:</p> <pre><code>SELECT * FROM mytable CROSS APPLY my_tvf(mytable.column1) tvf SELECT * FROM mytable CROSS APPLY ( SELECT TOP 5 * FROM othertable WHERE othertable.column2 = mytable.column1 ) q </code></pre></li> <li><p><code>EXCEPT</code> and <code>INTERSECT</code> operators: allow selecting conditions that include <code>NULL</code>s</p> <pre><code>DECLARE @var1 INT DECLARE @var2 INT DECLARE @var3 INT SET @var1 = 1 SET @var2 = NULL SET @var2 = NULL SELECT col1, col2, col3 FROM mytable INTERSECT SELECT @val1, @val2, @val3 -- selects rows with `col1 = 1`, `col2 IS NULL` and `col3 IS NULL` SELECT col1, col2, col3 FROM mytable EXCEPT SELECT @val1, @val2, @val3 -- selects all other rows </code></pre></li> <li><p><code>WITH ROLLUP</code> clause: selects a grand total for all grouped rows</p> <pre><code>SELECT month, SUM(sale) FROM mytable GROUP BY month WITH ROLLUP Month SUM(sale) --- --- Jan 10,000 Feb 20,000 Mar 30,000 NULL 60,000 -- a total due to `WITH ROLLUP` </code></pre></li> </ul>

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