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Storing time-series data, relational or non?

...evation. Correction It is not "filtering out the un-needed data"; it is selecting only the needed data. Yes, of course, if you have an Index to support the columns identified in the WHERE clause, it is very fast, and the query does not depend on the size of the table (grabbing 1,000 rows from a ...
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PDO MySQL: Use PDO::ATTR_EMULATE_PREPARES or not?

... I'm using caches on multiple levels anyway. You can always explicitly use SELECT SQL_CACHE <rest of statement> though. – Will Morgan May 4 '12 at 16:37 ...
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Why isn't SQL ANSI-92 standard better adopted over ANSI-89?

...shion. The "best" way to break is by compilation error. For example if you SELECT * somewhere, the addition of a column could fail to compile. The next best way to fail would be a run time error. It's worse because your users may see it, but it still gives you a nice warning that you've broken somet...
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One or more types required to compile a dynamic expression cannot be found. Are you missing referenc

... On your solution explorer window, right click to References, select Add Reference, go to .NET tab, find and add Microsoft.CSharp. share | improve this answer | ...
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how to set textbox value in jquery

...tched element. You cannot set the value of a textbox with that method. $(selector).load() returns the a jQuery object. By default an object is converted to [object Object] when treated as string. Further clarification: Assuming your URL returns 5. If your HTML looks like: <div id="foo"&g...
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run main class of Maven project [duplicate]

...d target dirs. The script search for classes with main method, offering a select to choose one (Example with mavenized JMeld project) $ mvnexec 1) org.jmeld.ui.JMeldComponent 2) org.jmeld.ui.text.FileDocument 3) org.jmeld.JMeld 4) org.jmeld.util.UIDefaultsPrint 5) org.jmeld.util.PrintPropert...
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How to add new column to MYSQL table?

...r comment it looks like your'e only adding the new column if: mysql_query("SELECT * FROM assessment"); returns false. That's probably not what you wanted. Try removing the '!' on front of $sql in the first 'if' statement. So your code will look like: $sql=mysql_query("SELECT * FROM assessment"); if...
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Convert data.frame column to a vector?

... The reminder of drop=FALSE is useful - this helps me in cases where I may select N columns from a data.frame, in those cases where N=1. – Iterator Aug 15 '11 at 20:42 ...
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Where does PostgreSQL store the database?

...e tablespaces, which might not be in that data directory, use this query. SELECT * FROM pg_tablespace; share | improve this answer | follow | ...
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Do I need Content-Type: application/octet-stream for file download?

...inline some would always use it, while others would use it if the user had selected "save link as" but not if they'd selected "save" while viewing (or at least IE used to be like that, it may have changed some years ago). sh...