所以我对网络开发还很陌生,而且之前我还没有真正使用过php和mysql。
我想查询我的数据库,以找出有多少结果对某个字段具有相同的值。我在考虑以下几点:
SELECT value_a, COUNT(*)
FROM table_a
WHERE value_a = (SELECT DISTINCT value_a FROM table_a)
但显然我的内部查询不能有多个值。我怎么能这样做?
答案 0 :(得分:1)
简单地做 -
如果您想检查单个值 -
ulimit -a | grep stack
或者每个值 -
int** a = new int*[r1];
for(int i = 0; i < r1; ++i)
{
a[i] = new int[c1];
}
a[0][0] = 10;
std::cout << a[0][0] << std::endl;
// Delete all the columns
for(int i = 0; i < r1; ++i)
delete[] a[i];
delete []a ;
答案 1 :(得分:0)
将您的结果(check_value)放入此查询
private static string _fileEncodingText;
public static string FileEncodingText
{
get { return _fileEncodingText; }
set
{
string oldValue = _fileEncodingText;
_fileEncodingText = value;
try
{
FileEncoding = Encoding.GetEncoding(value);
}
catch (System.Exception)
{
_fileEncodingText = oldValue;
FileEncoding = Encoding.UTF8;
}
}
}
public static Encoding FileEncoding { get; private set; }