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How do you use variables in a simple PostgreSQL script?
...e (http://www.postgresql.org/docs/9.1/static/sql-do.html )
DO $$
DECLARE v_List TEXT;
BEGIN
v_List := 'foobar' ;
SELECT *
FROM dbo.PubLists
WHERE Name = v_List;
-- ...
END $$;
Also you can get the last insert id:
DO $$
DECLARE lastid bigint;
BEGIN
INSERT INTO test (name) VALUES ('...
Get last n lines of a file, similar to tail
...nd the right number of '\n' characters.
def tail( f, lines=20 ):
total_lines_wanted = lines
BLOCK_SIZE = 1024
f.seek(0, 2)
block_end_byte = f.tell()
lines_to_go = total_lines_wanted
block_number = -1
blocks = [] # blocks of size BLOCK_SIZE, in reverse order starting
...
Remove property for all objects in array
...swered Oct 19 '17 at 21:47
piotr_czpiotr_cz
4,84111 gold badge2525 silver badges2121 bronze badges
...
Configure Microsoft.AspNet.Identity to allow email address as username
...
The C# version of this (in App_Code\IdentityModels.cs) is
public UserManager()
: base(new UserStore<ApplicationUser>(new ApplicationDbContext()))
{
UserValidator = new UserValidator<ApplicationUser>(this) { AllowOnlyAlphan...
Is there a way to delete a line in Visual Studio without cutting it?
...
@nathan_hc, that actually performs a cut, which pollutes the clipboard. (Try it yourself and paste after using CTRL-L)
– Kirk Woll
Sep 17 '10 at 2:39
...
What's the simplest way to test whether a number is a power of 2 in C++?
...a clever little bit hack to test that one and only one bit is set.
bool is_power_of_2(int x) {
return x > 0 && !(x & (x−1));
}
For more bit twiddling see here.
share
|
improv...
Convert to binary and keep leading zeros in Python
...n using format():
>>> import timeit
>>> timeit.timeit("f_(v, '#010b')", "v = 14; f_ = format") # use a local for performance
0.40298633499332936
>>> timeit.timeit("f'{v:#010b}'", "v = 14")
0.2850222919951193
But I'd use that only if performance in a tight loop matters,...
Coding in Other (Spoken) Languages
...nce I don't speak a word of that language, stuff could have been called var_123, var_562 or func_333 as well (and probably it would have been easier for me to remember the names or at least to have a chance of spelling them right without copying and pasting). Since this was a short, self-contained s...
Maximum length of the textual representation of an IPv6 address?
I want to store the data returned by $_SERVER["REMOTE_ADDR"] in PHP into a DB field, pretty simple task, really. The problem is that I can't find any proper information about the maximum length of the textual representation of an IPv6 address, which is what a webserver provides through $_SERVER...
Change Oracle port from port 8080
...<enter password if will not be visible>
Connected.
SQL> Exec DBMS_XDB.SETHTTPPORT(3010); [Assuming you want to have HTTP going to this port]
PL/SQL procedure successfully completed.
SQL>quit
then open browser and use 3010 port.
...