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Is it safe to use -1 to set all bits to true?
... on datasets of N bits by breaking it down into chunks of sizeof(unsigned)*CHAR_BIT bits each.
– MSalters
May 4 '09 at 7:22
2
...
How do I test which class an object is in Objective-C?
...objective-c runtime api:
#import <objc/runtime.h>
/* ... */
const char* className = class_getName([yourObject class]);
NSLog(@"yourObject is a: %s", className);
EDIT: In Swift
if touch.view is UIPickerView {
// touch.view is of type UIPickerView
}
...
PostgreSQL Crosstab Query
...ase, I believe it would look something like this:
CREATE TABLE t (Section CHAR(1), Status VARCHAR(10), Count integer);
INSERT INTO t VALUES ('A', 'Active', 1);
INSERT INTO t VALUES ('A', 'Inactive', 2);
INSERT INTO t VALUES ('B', 'Active', 4);
INSERT INTO t VALUES ('B', 'Inactive', 5);
SELECT...
How can I save application settings in a Windows Forms application?
...ings.Default.SomeProperty = 'value'; Settings.Default.Save(); works like a charm. Or is that because I've got User-settings?
– doekman
Jan 16 '12 at 10:34
4
...
Why is \r a newline for Vim?
From question How to replace a character for a newline in Vim? . You have to use \r when replacing text for a newline, like this
...
Psql list all tables
...log.pg_get_userbyid(d.datdba) as "Owner",
pg_catalog.pg_encoding_to_char(d.encoding) as "Encoding",
d.datcollate as "Collate",
d.datctype as "Ctype",
pg_catalog.array_to_string(d.datacl, E'\n') AS "Access privileges"
FROM pg_catalog.pg_database d
ORDER BY 1;
*************...
In .NET, which loop runs faster, 'for' or 'foreach'?
...Yup - I almost always prefer List<T> over arrays. The exceptions are char[] and byte[] which are more often treated as "chunks" of data rather than normal collections.
– Jon Skeet
May 27 '10 at 16:38
...
Convert Rows to columns using 'Pivot' in SQL Server
...rate the week number dynamically, your code will be:
DECLARE @cols AS NVARCHAR(MAX),
@query AS NVARCHAR(MAX)
select @cols = STUFF((SELECT ',' + QUOTENAME(Week)
from yt
group by Week
order by Week
FOR XML PATH(''), TYPE
...
NULL values inside NOT IN clause
... addressed in an excellent answer by @Brannon):
DECLARE @T TABLE
(
true CHAR(4) DEFAULT 'true' NOT NULL,
CHECK ( 3 IN (1, 2, 3, NULL )),
CHECK ( 3 NOT IN (1, 2, NULL ))
);
INSERT INTO @T VALUES ('true');
SELECT COUNT(*) AS tally FROM @T;
As per @Brannon's answer, the first constraint (usi...
Which encoding opens CSV files correctly with Excel on both Mac and Windows?
We have a web app that exports CSV files containing foreign characters with UTF-8, no BOM. Both Windows and Mac users get garbage characters in Excel. I tried converting to UTF-8 with BOM; Excel/Win is fine with it, Excel/Mac shows gibberish. I'm using Excel 2003/Win, Excel 2011/Mac.
Here's all the ...