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Creating a constant Dictionary in C#
...y a nice one; remember that according to the C# specification, switch-case tables are compiled to constant hash jump tables. That is, they are constant dictionaries, not a series of if-else statements. So consider a switch-case statement like this:
switch (myString)
{
case "cat": return 0;
ca...
PHP: How to remove all non printable characters in a string?
...SCII?
If your Tardis just landed in 1963, and you just want the 7 bit printable ASCII chars, you can rip out everything from 0-31 and 127-255 with this:
$string = preg_replace('/[\x00-\x1F\x7F-\xFF]/', '', $string);
It matches anything in range 0-31, 127-255 and removes it.
8 bit extended ASCI...
Difference between HBase and Hadoop/HDFS
...able, distributed database that supports structured data storage for large tables. Just as Bigtable leverages the distributed data storage provided by the Google File System, Apache HBase provides Bigtable-like capabilities on top of Hadoop and HDFS.
When to use HBase:
If your application has a v...
Add a column to a table, if it does not already exist
I want to write a query for MS SQL Server that adds a column into a table. But I don't want any error display, when I run/execute the following query.
...
Where to learn about VS debugger 'magic names'
... suffix ("current", "state", and so on) so that you don't have to have the table above memorized when reading the metadata.
I is an optional unique number
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How do you connect to multiple MySQL databases on a single webpage?
...ery database 1 pass the first link identifier:
mysql_query('select * from tablename', $dbh1);
and for database 2 pass the second:
mysql_query('select * from tablename', $dbh2);
If you do not pass a link identifier then the last connection created is used (in this case the one represented by $d...
How to check the version before installing a package using apt-get?
...-server
redis-server:
Installed: (none)
Candidate: 2:2.8.4-2
Version table:
2:2.8.4-2 0
500 http://us.archive.ubuntu.com/ubuntu/ trusty/universe amd64 Packages
apt-get install -s <package-name>
$ apt-get install -s redis-server
NOTE: This is only a simulation!
apt-g...
How to list records with date from the last 10 days?
...hy don't you just try it?
The standard ANSI SQL format would be:
SELECT Table.date
FROM Table
WHERE date > current_date - interval '10' day;
I prefer that format as it makes things easier to read (but it is the same as current_date - 10).
...
How to change field name in Django REST Framework
... blank=True)
objects = models.GeoManager()
class Meta:
db_table = u'p_park'
def __unicode__(self):
return '%s' % self.name
Here is Serializer for Park Model, ParkSerializer. This changes the name of alternate_name to location.
class ParkSerializer(serializers.ModelS...
Renaming columns in pandas
...place=True is necessary to avoid that gotchya.
– irritable_phd_syndrom
Jul 14 '17 at 13:24
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