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delete vs delete[] operators in C++
... I wonder if using delete on a new[] array of primitive types like int or char (no constructor/destructor) necessarily leads to undefined behavior, too. It seems the array size isn't stored anywhere when using primitive types.
– thomiel
Jul 6 '14 at 11:16
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Ruby: Can I write multi-line string with no concatenation?
... HEREDOC syntax (via this link):
p <<END_SQL.gsub(/\s+/, " ").strip
SELECT * FROM users
ORDER BY users.id DESC
END_SQL
# >> "SELECT * FROM users ORDER BY users.id DESC"
The latter would mostly be for situations that required more flexibility in the processing. I personall...
Difference between float and decimal data type
...0,2), b float);
mysql> insert into numbers values (100, 100);
mysql> select @a := (a/3), @b := (b/3), @a * 3, @b * 3 from numbers \G
*************************** 1. row ***************************
@a := (a/3): 33.333333333
@b := (b/3): 33.333333333333
@a + @a + @a: 99.9999999990000000000000...
Select count(*) from multiple tables
How can I select count(*) from two different tables (call them tab1 and tab2 ) having as result:
18 Answers
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How to get the Full file path from URI
...but if i do it like the MediaStore Solution, it won't work if the app user selects eg Astro as browser, instead of Music Player. How do I solve this?
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Want to find records with no associated records in Rails
... get everyone with no friends in the first case:
Person.where('id NOT IN (SELECT DISTINCT(person_id) FROM friends)')
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PHP/MySQL insert row then get 'id'
...);
See mysqli_insert_id().
Whatever you do, don't insert and then do a "SELECT MAX(id) FROM mytable". Like you say, it's a race condition and there's no need. mysqli_insert_id() already has this functionality.
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What does “fragment” mean in ANTLR?
... and results:
Alphabet.g4 (Case1)
grammar Alphabet;
content : (rule0|ANYCHAR)* EOF;
rule0 : RULE1 | RULE2 | RULE3 ;
RULE1 : [A-C]+ ;
RULE2 : [DEF]+ ;
RULE3 : ('G'|'H'|'I')+ ;
ANYCHAR : . -> skip;
Result:
# Input data (for reference)
# ABBCCCDDDDEEEEE ABCDE
# FFGGHHIIJJKK FGHIJK
# ABCDEF...
Get selected text from a drop-down list (select box) using jQuery
How can I get the selected text (not the selected value) from a drop-down list in jQuery?
34 Answers
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Python glob multiple filetypes
... not possible. you can use only:
* matches everything
? matches any single character
[seq] matches any character in seq
[!seq] matches any character not in seq
use os.listdir and a regexp to check patterns:
for x in os.listdir('.'):
if re.match('.*\.txt|.*\.sql', x):
print x
...
