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Difference between Fact table and Dimension table?
... some cases.
More details:
Fact and dimension tables appear in a what is commonly known as a Star Schema. 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 v...
MySQL, better to insert NULL or empty string?
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How many characters can UTF-8 encode?
..., Coptic, Armenian, Hebrew, Arabic, Syriac and Tāna alphabets, as well as Combining Diacritical Marks.
Three bytes are needed for characters in the rest of the Basic Multilingual Plane, which contains virtually all characters in common use[12] including most Chinese, Japanese and Korean [CJK] ...
getting date format m-d-Y H:i:s.u from milliseconds
...s",$date_array[1]);
echo "Date: $date:" . $date_array[0]."<br>";
Recommended and use dateTime() class from referenced:
$t = microtime(true);
$micro = sprintf("%06d",($t - floor($t)) * 1000000);
$d = new DateTime( date('Y-m-d H:i:s.'.$micro, $t) );
print $d->format("Y-m-d H:i:s.u"); // ...
Painless way to install a new version of R?
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Just for completeness, there are some ways to prevent you from having this problem. As Dirk said, save your packages in another directory on your computer.
install.packages("thepackage",lib="/path/to/directory/with/libraries")
You...
When is it appropriate to use C# partial classes?
...ner would spit out all of the code inside of a region with strongly worded comments about not modifying the code. It had to insert all sorts of heuristics to find the generated code for later processing. Now it can simply open the designer.cs file and have a high degree of confidence that it contai...
How do I calculate percentiles with python/numpy?
... You can use it as an aggregation function as well, e.g. to compute the tenth percentile of each group of a value column by key, use df.groupby('key')[['value']].agg(lambda g: np.percentile(g, 10))
– patricksurry
Nov 26 '13 at 17:25
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Best way to trim strings after data entry. Should I create a custom model binder?
...ontrollerContext,
ModelBindingContext bindingContext,
System.ComponentModel.PropertyDescriptor propertyDescriptor, object value)
{
if (propertyDescriptor.PropertyType == typeof(string))
{
var stringValue = (string)value;
if (!string.IsNullOrWhiteSpace(st...
MySQL Error 1093 - Can't specify target table for update in FROM clause
... use in the SELECT part.
This behaviour is documented at:
http://dev.mysql.com/doc/refman/5.6/en/update.html
Maybe you can just join the table to itself
If the logic is simple enough to re-shape the query, lose the subquery and join the table to itself, employing appropriate selection criteria. Th...