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PostgreSQL “DESCRIBE TABLE”
... 'table' or \ds 'sequence' and so on)
The SQL standard way, as shown here:
select column_name, data_type, character_maximum_length, column_default, is_nullable
from INFORMATION_SCHEMA.COLUMNS where table_name = '<name of table>';
It's supported by many db engines.
...
What's the need of array with zero elements?
...ther words, if you have:
struct something
{
/* other variables */
char data[];
}
struct something *var = malloc(sizeof(*var) + extra);
You can access var->data with indices in [0, extra). Note that sizeof(struct something) will only give the size accounting for the other variables, i....
Check if a string contains a number
...n, like this
>>> def hasNumbers(inputString):
... return any(char.isdigit() for char in inputString)
...
>>> hasNumbers("I own 1 dog")
True
>>> hasNumbers("I own no dog")
False
Alternatively you can use a Regular Expression, like this
>>> import re
>&g...
Multiple INSERT statements vs. single INSERT with multiple VALUES
...t
One place where this information is leveraged is shown by @Lieven here
SELECT *
FROM (VALUES ('Lieven1', 1),
('Lieven2', 2),
('Lieven3', 3))Test (name, ID)
ORDER BY name, 1/ (ID - ID)
Because at compile time it can determine that the Name column has no duplicates it...
How to check if a char is equal to an empty space?
...
if (c == ' ')
char is a primitive data type, so it can be compared with ==.
Also, by using double quotes you create String constant (" "), while with single quotes it's a char constant (' ').
...
字符串指针变量与字符数组的区别 - C/C++ - 清泛网 - 专注C/C++及内核技术
... 设有定义字符型指针变量与字符数组的语句如下： char *pc ,str[100]; 则系统...使用字符串指针变量与字符数组的区别
（1）分配内存
设有定义字符型指针变量与字符数组的语句如下：
char *pc ,str[100];
则系...
How do you print out a stack trace to the console/log in Cocoa?
...#import <UIKit/UIKit.h>
#import "AppDelegate.h"
int main(int argc, char *argv[])
{
@autoreleasepool {
int retval;
@try{
retval = UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));
}
@catch (NSException *exception)
...
How can I pass a member function where a free function is expected?
...n<void(int, int)> fun)
{
fun(1, 1);
}
int main (int argc, const char * argv[])
{
...
aClass a;
auto fp = std::bind(&aClass::test, a, _1, _2);
function1(fp);
return 0;
}
share
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...
See all breakpoints in Visual Studio 2010+
...
In Visual Studio 2017, Ctrl+D duplicates the current selection and Ctrl+B adds a new breakpoint at the current line. Ctrl+F9 does nothing.
– Malcolm
May 7 '19 at 16:16
...
Bytes of a string in Java
...
A string is a list of characters (i.e. code points). The number of bytes taken to represent the string depends entirely on which encoding you use to turn it into bytes.
That said, you can turn the string into a byte array and then look at its si...