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Generating a UUID in Postgres for Insert statement?
...d to run psql -d dbname -f SHAREDIR/contrib/module.sql and now it works!!! select uuid_generate_v1(); returns 1 now now. Thanks so much!
– anon58192932
Sep 29 '12 at 22:13
5
...
Types in MySQL: BigInt(20) vs Int(20)
...E TABLE foo ( bar INT(20) ZEROFILL );
INSERT INTO foo (bar) VALUES (1234);
SELECT bar from foo;
+----------------------+
| bar |
+----------------------+
| 00000000000000001234 |
+----------------------+
It's a common source of confusion for MySQL users to see INT(20) and assume ...
How to make an OpenGL rendering context with transparent background?
... 0);
assert(hbmpDIB);
assert(bmp_cnt);
if(hbmpDIB)
SelectObject(pdcDIB, hbmpDIB);
}
BOOL CreateHGLRC()
{
DWORD dwFlags = PFD_SUPPORT_OPENGL | PFD_DRAW_TO_BITMAP;
PIXELFORMATDESCRIPTOR pfd ;
memset(&pfd,0, sizeof(PIXELFORMATDESCRIPTOR)) ;
pfd.nSize = size...
Extract date (yyyy/mm/dd) from a timestamp in PostgreSQL
... to a date by suffixing it with ::date. Here, in psql, is a timestamp:
# select '2010-01-01 12:00:00'::timestamp;
timestamp
---------------------
2010-01-01 12:00:00
Now we'll cast it to a date:
wconrad=# select '2010-01-01 12:00:00'::timestamp::date;
date
------------
201...
Program only crashes as release build — how to debug?
...sh do an Attach To Process (Tools menu on Visual Studio).
After the crash, select the option to launch debugger.
When asked to point to PDB files, browse to find them. If the PDB's were put in the same output folder as your E
How to handle Objective-C protocols that contain properties?
...hInteger:(factor*amount)];
}
// <<
@end
int main(int argc, const char * argv[])
{
@autoreleasepool {
Person *duncan=[[Person alloc]initConforming];
duncan.firstname=@"Duncan";
duncan.lastname=@"Smith";
[Viewer printLargeDescription:duncan];
S...
Concatenate multiple result rows of one column into one, group by another column [duplicate]
...Simpler with the aggregate function string_agg() (Postgres 9.0 or later):
SELECT movie, string_agg(actor, ', ') AS actor_list
FROM tbl
GROUP BY 1;
The 1 in GROUP BY 1 is a positional reference and a shortcut for GROUP BY movie in this case.
string_agg() expects data type text as input. Other ...
Use '=' or LIKE to compare strings in SQL?
...
To see the performance difference, try this:
SELECT count(*)
FROM master..sysobjects as A
JOIN tempdb..sysobjects as B
on A.name = B.name
SELECT count(*)
FROM master..sysobjects as A
JOIN tempdb..sysobjects as B
on A.name LIKE B.name
Comparing strings with '=' is muc...
How can I hash a password in Java?
...te[16];
random.nextBytes(salt);
KeySpec spec = new PBEKeySpec("password".toCharArray(), salt, 65536, 128);
SecretKeyFactory f = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
byte[] hash = f.generateSecret(spec).getEncoded();
Base64.Encoder enc = Base64.getEncoder();
System.out.printf("salt: %s...
Difference between one-to-many and many-to-one relationship
... Bar references Foo
Not the other way around
CREATE TABLE Foo (
Foo CHAR(10) NOT NULL, -- primary key
Name CHAR(30) NOT NULL
CONSTRAINT PK -- constraint name
PRIMARY KEY (Foo) -- pk
)
CREATE TABLE Bar (
Bar CHAR(10) NOT NULL, -- primary key
...