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Displaying posts with tag: union all (reset)

MariaDB 10.1.1 Overview and Highlights
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MariaDB 10.1.1 was recently released, and is available for download here:

https://downloads.mariadb.org/mariadb/10.1.1/

This is the second alpha release of MariaDB 10.1, so there are a lot of new changes and functionalities added, and many, many bugs fixed (I counted 637). Since it’s alpha, I’ll only cover the major changes and additions, as there are a lot of great new features, and omit covering any of the bug fixes (feel free to browse them all here).

To me, these are …

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How to Optimize MySQL UNION For High Speed
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Join 6100 others and follow Sean Hull on twitter @hullsean. There are two ways to speedup UNIONs in a MySQL database. First use UNION ALL if at all possible, and second try to push down your conditions. [mytweetlinks] 1. UNION ALL is much faster than UNION How does a UNION work? Imagine you have two [...]

Optimizing the MySQL IN() Comparison Operations Which Include the Indexed Field
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The MySQL IN() Comparison Operator is said to be very quick if all the values are constants (the values are then evaluated and sorted first, and the search is done using a binary search). However, what if the field which the IN clause refers to, is part of the index used to execute the query? […]

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