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Insert into … values ( SELECT … FROM … )
...SERT from another table I did the following in SQLite3:
INSERT INTO column_1 ( val_1, val_from_other_table )
VALUES('val_1', (SELECT val_2 FROM table_2 WHERE val_2 = something))
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MySQL check if a table exists without throwing an exception
...PDO syntax for it, but this seems pretty straight-forward:
$result = mysql_query("SHOW TABLES LIKE 'myTable'");
$tableExists = mysql_num_rows($result) > 0;
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...
What exactly are late static bindings in PHP?
...self::, parent::, static::, or, if going up in the class hierarchy, forward_static_call(). The function get_called_class() can be used to retrieve a string with the name of the called class and static:: introduces its scope.
...
Get names of all keys in the collection
...You could do this with MapReduce:
mr = db.runCommand({
"mapreduce" : "my_collection",
"map" : function() {
for (var key in this) { emit(key, null); }
},
"reduce" : function(key, stuff) { return null; },
"out": "my_collection" + "_keys"
})
Then run distinct on the resulting collecti...
I want to delete all bin and obj folders to force all projects to rebuild everything
... you can use this:
Get-ChildItem .\ -include bin,obj -Recurse | foreach ($_) { remove-item $_.fullname -Force -Recurse }
as seen in Robert H's answer below - just make sure you give him credit for the powershell answer rather than me if you choose to up-vote anything :)
It would of course be wis...
Download file from web in Python 3
....request
...
# Download the file from `url` and save it locally under `file_name`:
urllib.request.urlretrieve(url, file_name)
import urllib.request
...
# Download the file from `url`, save it in a temporary directory and get the
# path to it (e.g. '/tmp/tmpb48zma.txt') in the `file_name` variable:...
Download the Android SDK components for offline install
...available
Fetching https://dl-ssl.google.com/android/repository/addons_list-2.xml
Fetched Add-ons List successfully
Fetching URL: https://dl-ssl.google.com/android/repository/repository-7.xml
Validate XML: https://dl-ssl.google.com/android/repository/repository-7.xml
Parse XML: https...
Will using 'var' affect performance?
...it ([0] string string1,
[1] string string2)
IL_0000: nop
IL_0001: ldc.i4.s 9
IL_0003: newarr [mscorlib]System.Char
IL_0008: newobj instance void [mscorlib]System.String::.ctor(char[])
IL_000d: stloc.0
IL_00...
What is the size of an enum in C?
... having only that, the following is valid i think: enum { LAST = INT_MAX, LAST1, LAST2 }; so LAST2 is not representable in int, but there wasn't an expression defining it.
– Johannes Schaub - litb
Dec 14 '08 at 1:33
...
“is” operator behaves unexpectedly with integers
...tively rare. Here's an example (will work in Python 2 and 3) e.g.
SENTINEL_SINGLETON = object() # this will only be created one time.
def foo(keyword_argument=None):
if keyword_argument is None:
print('no argument given to foo')
bar()
bar(keyword_argument)
bar('baz')
def b...