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How do I lowercase a string in C?
...ent such a function. So yes, just loop through the string and convert each character to lowercase.
Something trivial like this:
#include <ctype.h>
for(int i = 0; str[i]; i++){
str[i] = tolower(str[i]);
}
or if you prefer one liners, then you can use this one by J.F. Sebastian:
for ( ;...
Importance of varchar length in MySQL table
...
Anytime your select query uses a temporary table (group and order by operations, among other things) it will convert varchar(200) to a char(200) and performance will suffer.
– Jamie
Feb 7 '13 at 20:1...
Read Excel File in Python
...ues for a given column
values = df['Arm_id'].values
#get a data frame with selected columns
FORMAT = ['Arm_id', 'DSPName', 'Pincode']
df_selected = df[FORMAT]
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Store boolean value in SQLite
...TO foo VALUES("0.0");
sqlite> INSERT INTO foo VALUES("1.0");
sqlite> select mycolumn, typeof(mycolumn) from foo;
0|integer
1|integer
0|integer
1|integer
0|integer
1|integer
and some that will fail:
sqlite> INSERT INTO foo VALUES("-1");
Error: constraint failed
sqlite> INSERT INTO foo ...
Why unsigned integer is not available in PostgreSQL?
...< 65536);
Here is what psql gives when I try to abuse the type.
DS1=# select (346346 :: uint2);
ERROR: value for domain uint2 violates check constraint "uint2_check"
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How To Test if Type is Primitive
...
where t.IsValueType
select typeof (Nullable<>).MakeGenericType(t);
List = types.Concat(nullTypes).ToArray();
}
public static bool Test(Type type)
{
if (List.Any(x => x.IsAssignableFrom(type))...
LISTAGG in Oracle to return distinct values
...
19c and later:
select listagg(distinct the_column, ',') within group (order by the_column)
from the_table
18c and earlier:
select listagg(the_column, ',') within group (order by the_column)
from (
select distinct the_column
from t...
What is the size of column of int(11) in mysql in bytes?
...ytes (64 bit).
The length just specifies how many characters to pad when selecting data with the mysql command line client. 12345 stored as int(3) will still show as 12345, but if it was stored as int(10) it would still display as 12345, but you would have the option to pad the first five digits. ...
Check if a string has white space
...) {
return /\s/g.test(s);
}
This will also check for other white space characters like Tab.
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Why can't C compilers rearrange struct members to eliminate alignment padding? [duplicate]
...erent type than the one seen by the compiler, for example:
struct S {
char a;
int b;
char c;
};
struct S_head {
char a;
};
struct S_ext {
char a;
int b;
char c;
int d;
char e;
};
struct S s;
struct S_head *head = (struct S_head*)&s;
fn1(head);
struct S_ex...