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What's the best practice for primary keys in tables?
...fer a numeric type because numeric types are stored in a much more compact format than character formats. This is because most primary keys will be foreign keys in another table as well as used in multiple indexes. The smaller your key, the smaller the index, the less pages in the cache you will use...
Unicode, UTF, ASCII, ANSI format differences
...y particular encoding.
UTF-16: 2 bytes per "code unit". This is the native format of strings in .NET, and generally in Windows and Java. Values outside the Basic Multilingual Plane (BMP) are encoded as surrogate pairs. These used to be relatively rarely used, but now many consumer applications will ...
Why is Linux called a monolithic kernel?
...comment was somewhat tongue-in-cheek - the "hybrid" designation seems so information-free as to be useless.
– caf
Nov 28 '09 at 1:31
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show ...
Change Activity's theme programmatically
...d this one ex : pastebin.com/r93qrRDG edit : use pastebin to have a better formatting
– SocialSupaCrew
Oct 8 '18 at 16:18
...
What is the preferred syntax for initializing a dict: curly brace literals {} or the dict() function
... the dictionary, but are not one of the keys), then you'll need the second form. In that case, you can initialize your dictionary with keys having arbitrary characters, one at a time, like so:
class mydict(dict): pass
a = mydict()
a["b=c"] = 'value'
a.test = False
...
Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]
...trix -- e.g. to plot
#' the data via image() later on. Two of the columns form the row and
#' col dimensions of the matrix. The third column provides values for
#' the matrix.
#'
#' @param data data.frame: input data
#' @param rowtitle string: row-dimension; name of the column in data, which disti...
Preferred method to store PHP arrays (json_encode vs serialize)
...f ($jsonTime < $serializeTime) {
printf("json_encode() was roughly %01.2f%% faster than serialize()\n", ($serializeTime / $jsonTime - 1) * 100);
}
else if ($serializeTime < $jsonTime ) {
printf("serialize() was roughly %01.2f%% faster than json_encode()\n", ($jsonTime / $serializeTime ...
How do I raise the same Exception with a custom message in Python?
...
Depending on what the purpose is, you can also opt for adding the extra information under your own variable name. For both python2 and python3:
try:
try:
raise ValueError
except ValueError as err:
err.extra_info = "hello"
raise
except ValueError as e:
print(" error...
Share data between AngularJS controllers
I'm trying to share data across controllers. Use-case is a multi-step form, data entered in one input is later used in multiple display locations outside the original controller. Code below and in jsfiddle here .
...
Find a string by searching all tables in SQL Server Management Studio 2008
...(QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME))
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE'
AND QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME) > @TableName
AND OBJECTPROPERTY(
OBJECT_ID...