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Difference between Fact table and Dimension table?
...hema. A primary purpose of star schema is to simplify a complex normalized set of tables and consolidate data (possibly from different systems) into one database structure that can be queried in a very efficient way.
On its simplest form, it contains a fact table (Example: StoreSales) and a one or ...
How do I restart nginx only after the configuration test was successful on Ubuntu?
When I restart the nginx service on a command line on an Ubuntu server, the service crashes when a nginx configuration file has errors. On a multi-site server this puts down all the sites, even the ones without configuration errors.
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How many characters can UTF-8 encode?
...e as ascii). But that only requires 7 bits. If the highest ("sign") bit is set, this indicates the start of a multi-byte sequence; the number of consecutive high bits set indicates the number of bytes, then a 0, and the remaining bits contribute to the value. For the other bytes, the highest two bi...
must appear in the GROUP BY clause or be used in an aggregate function
... @amenzhinsky What do you mean? If one wants to have the result set sorted with a different order than BY cname ?
– ypercubeᵀᴹ
Nov 26 '14 at 13:19
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I forgot the password I entered during postgres installation
... (during the installation) the password to the default user of Postgres. I can't seem to be able to run it and I get the following error:
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How do you rename a MongoDB database?
...ery single collection and index includes the database name, so to rename a set of database files, every single namespace string would have to be rewritten. This impacts:
the .ns file
every single numbered file for the collection
the namespace for every index
internal unique names of ea...
Best way to trim strings after data entry. Should I create a custom model binder?
...class TrimModelBinder : DefaultModelBinder
{
protected override void SetProperty(ControllerContext controllerContext,
ModelBindingContext bindingContext,
System.ComponentModel.PropertyDescriptor propertyDescriptor, object value)
{
if (propertyDescriptor.PropertyType == ...
Why are Subjects not recommended in .NET Reactive Extensions?
...s managing Subjects.
Observable.Create gives you a clean pattern for lazy setup and clean teardown. How do you achieve this with a class wrapping a Subject? You need some kind of Start method... how do you know when to call it? Or do you just always start it, even when no one is listening? And when...
Disable mouse scroll wheel zoom on embedded Google Maps
... this should be marked as the answer, although probably easier to set the overlay as absolutely positioned to a parent container and then just width 100% height 100%, also doesnt need a background property.
– hcharge
Aug 8 '14 at 10:56
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Equivalent of .try() for a hash to avoid “undefined method” errors on nil? [duplicate]
In Rails we can do the following in case a value doesn't exist to avoid an error:
12 Answers
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