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How do I remove all specific characters at the end of a string in PHP?
How do I remove the last character only if it's a period?
9 Answers
9
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Regex lookahead, lookbehind and atomic groups
...tive or negative) and discards the matched portion. They don't consume any character - the matching for regex following them (if any), will start at the same cursor position.
Read regular-expression.info for more details.
Positive lookahead:
Syntax:
(?=REGEX_1)REGEX_2
Match only if REGEX_...
Oracle “(+)” Operator
...dize OUTER joins.
The query would be re-written in ANSI-92 syntax as:
SELECT ...
FROM a
LEFT JOIN b ON b.id = a.id
This link is pretty good at explaining the difference between JOINs.
It should also be noted that even though the (+) works, Oracle recommends not using it:
Oracle re...
How many bytes does one Unicode character take?
...fer UTF-16 over UTF-8, for instance. Developers of different software may select different encodings based upon which Unicode characters are more likely to be used. In China/Japan for instance, UTF-16 (2-bytes) makes more sense than UTF-8 for them, because the same characters often would need twice...
Is std::vector so much slower than plain arrays?
... created. What happens if we change Pixel to:
struct Pixel
{
unsigned char r, g, b;
};
Result: about 10% faster. Still slower than an array. Hm.
# ./vector
UseArray completed in 3.239 seconds
UseVector completed in 5.567 seconds
Idea #4 - Use iterator instead of loop index
How about usin...
List all sequences in a Postgres db 8.1 with SQL
...
The following query gives names of all sequences.
SELECT c.relname FROM pg_class c WHERE c.relkind = 'S';
Typically a sequence is named as ${table}_id_seq. Simple regex pattern matching will give you the table name.
To get last value of a sequence use the following query:...
Regular expression to match a word or its prefix
...
Because the person who posted the question selected the first answer that came in, and didn't bother to switch to mine when my vastly superior answer came in later. You can ask the questioner via comment under the question to change their answer selection to this one...
How do I best silence a warning about unused variables?
...tion is more convenient, although less cleaner.
– cbuchart
Jul 17 '14 at 6:57
I think simpler is better, commenting ou...
How do I extract text that lies between parentheses (round brackets)?
...
Honestly, this should've been selected as the answer.
– Pat Lindley
Jan 11 '13 at 18:58
1
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T-SQL datetime rounded to nearest minute and nearest hours with using functions
...
declare @dt datetime
set @dt = '09-22-2007 15:07:38.850'
select dateadd(mi, datediff(mi, 0, @dt), 0)
select dateadd(hour, datediff(hour, 0, @dt), 0)
will return
2007-09-22 15:07:00.000
2007-09-22 15:00:00.000
The above just truncates the seconds and minutes, producing the resu...