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Extracting an attribute value with beautifulsoup
...have a question about parsing the output which i a long bunch of non-ASCII chars but I will ask this in a separate question.
– Barnabe
Apr 10 '10 at 7:33
3
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When should I use perror(“…”) and fprintf(stderr, “…”)?
...
perror(const char *s): prints the string you give it followed by a string that describes the current value of errno.
stderr: it's an output stream used to pipe your own error messages to (defaults to the terminal).
Relevant:
char *stre...
Difference between EXISTS and IN in SQL?
...way to avoid counting:
--this statement needs to check the entire table
select count(*) from [table] where ...
--this statement is true as soon as one match is found
exists ( select * from [table] where ... )
This is most useful where you have if conditional statements, as exists can be a lot ...
CHECK constraint in MySQL is not working
...GER `test_before_insert` BEFORE INSERT ON `Test`
FOR EACH ROW
BEGIN
IF CHAR_LENGTH( NEW.ID ) < 4 THEN
SIGNAL SQLSTATE '12345'
SET MESSAGE_TEXT := 'check constraint on Test.ID failed';
END IF;
END$$
DELIMITER ;
Prior to MySQL 5.5 you had to cause an error, e.g. ca...
Detecting which UIButton was pressed in a UITableView
...)metaData:(id)target
Enjoy
#import <objc/runtime.h>
static char const * const kMetaDic = "kMetaDic";
#pragma mark - Getters / Setters
- (id)metaData:(id)target {
return objc_getAssociatedObject(target, kMetaDic);
}
- (void)setMetaData:(id)target withObject:(id)newObj {
...
Passing an array to a query using a WHERE clause
...y external input is sanitized.
$ids = join("','",$galleries);
$sql = "SELECT * FROM galleries WHERE id IN ('$ids')";
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C: Run a System Command and Get Output? [duplicate]
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#include <stdio.h>
#include <stdlib.h>
int main( int argc, char *argv[] )
{
FILE *fp;
char path[1035];
/* Open the command for reading. */
fp = popen("/bin/ls /etc/", "r");
if (fp == NULL) {
printf("Failed to run command\n" );
exit(1);
}
/* Read the output a ...
What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
The "N+1 selects problem" is generally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
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string.split - by multiple character delimiter
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This presupposes, that there are both characters right? What if I want to split by either "[" or "]"? From my tests so far I guess thats a different story, right?
– C4d
Mar 7 '16 at 15:28
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How do you implement a class in C? [closed]
...n(Object *self);
/// Person.h
typedef struct Person {
Object obj;
char *name;
} Person;
int Person_init(Person *self, char *name);
int Person_greet(Person *self);
int Person_clean(Person *self);
/// Object.c
#include "object.h"
int Object_init(Object *self)
{
self->uuid = uuid_new...