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This Is Your Brain On Informatics: MariaDB

705 bytes added, 05:38, 23 October 2013
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<p>This data table was uploaded as a TSV (tab separated values) file.</p>
<p>LOAD DATA INFILE '[data table pathname]' INTO TABLE `test` FIELDS TERMINATED BY '\t' OPTIONALLY ENCLOSED BY '"' LINES TERMINATED BY '\r\n' IGNORE 1 LINE</p>
 
===Answer to In-Class Question===
 
<p>Q: Find the maximums in column 2 of quintiles based on column 1 </p>
 
<p>
The following will create a temporary table that will order [var1] and also create a column with an counter variable named "id".
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A: CREATE TEMPORARY TABLE `rank` (id BIGINT UNSIGNED AUTO_INCREMENT PRIMARY KEY) SELECT [var1],[var2] FROM `test` WHERE [var3] = "string" AND [var1] <10000000 ORDER BY [var1];
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Then the use of the next command will need to be repeated for each quintile to find the maximum for each one.
<br /><br />
A: SELECT MAX([var2]) FROM `rank` WHERE id BETWEEN [calculated lower bound of quintile] AND [calculated upper bound of quintile];
</p>
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