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How can mixed data types (int, float, char, etc) be stored in an array?
...minated union, aka tagged union.
struct {
enum { is_int, is_float, is_char } type;
union {
int ival;
float fval;
char cval;
} val;
} my_array[10];
The type member is used to hold the choice of which member of the union is should be used for each array element. ...
Is there a way to specify how many characters of a string to print out using printf()?
Is there a way to specify how many characters of a string to print out (similar to decimal places in int s)?
8 Answers
...
How to read a CSV file into a .NET Datatable
...e(path);
string fileName = Path.GetFileName(path);
string sql = @"SELECT * FROM [" + fileName + "]";
using(OleDbConnection connection = new OleDbConnection(
@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + pathOnly +
";Extended Properties=\"Text;HDR=" + h...
PostgreSQL Crosstab Query
... - not fit for missing attributes
crosstab(text) with 1 input parameter:
SELECT *
FROM crosstab(
'SELECT section, status, ct
FROM tbl
ORDER BY 1,2' -- needs to be "ORDER BY 1,2" here
) AS ct ("Section" text, "Active" int, "Inactive" int);
Returns:
Section | Active | Inacti...
Which are more performant, CTE or temporary tables?
...(A INT IDENTITY PRIMARY KEY, B INT , F CHAR(8000) NULL);
INSERT INTO T(B)
SELECT TOP (1000000) 0 + CAST(NEWID() AS BINARY(4))
FROM master..spt_values v1,
master..spt_values v2;
Example 1
WITH CTE1 AS
(
SELECT A,
ABS(B) AS Abs_B,
F
FROM T
)
SELECT *
FROM CTE1
WHERE A = 780
...
Conveniently Declaring Compile-Time Strings in C++
...y cumbersome, as the string needs to be declared as a variadic sequence of characters, e.g.
15 Answers
...
convert a char* to std::string
...g to store data retrieved by fgets() . To do this I need to convert the char* return value from fgets() into an std::string to store in an array. How can this be done?
...
uint8_t can't be printed with cout
...
It doesn't really print a blank, but most probably the ASCII character with value 5, which is non-printable (or invisible). There's a number of invisible ASCII character codes, most of them below value 32, which is the blank actually.
You have to convert aa to unsigned int to output t...
How to get rid of `deprecated conversion from string constant to ‘char*’` warnings in GCC?
...ch case @John's answer below, about changing the signature to accept const char*, is more correct.
– jcwenger
Jun 27 '14 at 15:07
216
...
Fetch the row which has the Max value for a column
... multiple rows for the userid where the maximum date is on multiple rows.
select userid,
my_date,
...
from
(
select userid,
my_date,
...
max(my_date) over (partition by userid) max_my_date
from users
)
where my_date = max_my_date
"Analytic functions rock"
Edi...