5.2.43hdfql_subcursor_get_bigint
Syntax
long long *hdfql_subcursor_get_bigint(const HDFQL_CURSOR *cursor)
Description
Get the current element of the subcursor in use as a BIGINT. In other words, the current element is interpreted as a “long long” C data type and returned as a pointer to such type. If the result subset is empty or the subcursor is located before or after the first or last element of the result subset, the returned element is NULL.
Parameter(s)
cursor – pointer to a cursor to get the current element of the subcursor in use as a BIGINT. If the pointer is NULL (in C), the current element of the subcursor of the cursor in use is returned instead. The equivalent of a NULL pointer in C++, Java, Python, C#, Fortran, R, and MATLAB HDFql wrappers is NULL, null, None, null, NULL(), NULL, and NaN, respectively. While in C cursor is mandatory, in C++, Java, Python, C#, Fortran, R, and MATLAB it is optional (when not specified, the current element of the subcursor of the cursor in use is returned instead).
Return
long long * – pointer to the current element of the subcursor. If there is no current element, the pointer will be NULL.
Example(s)
// create an HDF5 dataset named "my_dataset" of data type variable-length long long of one dimension (size 3)
hdfql_execute("CREATE DATASET my_dataset AS VARBIGINT(3)");
// insert (i.e. write) values into dataset "my_dataset"
hdfql_execute("INSERT INTO my_dataset VALUES((5, 2), (8), (4, 3, 9))");
// select (i.e. read) data from dataset "my_dataset" and populate cursor in use with it
hdfql_execute("SELECT FROM my_dataset");
// move the cursor in use to next position within the result set (i.e. first position)
hdfql_cursor_next(NULL);
// display current element of the cursor in use as a long long (should be "Current element of cursor is 5")
printf("Current element of cursor is %lld\n", *hdfql_cursor_get_bigint(NULL));
// move the subcursor in use to next position within the result subset (i.e. first position)
hdfql_subcursor_next(NULL);
// display current element of the subcursor in use as a long long (should be "Current element of subcursor is 5")
printf("Current element of subcursor is %lld\n", *hdfql_subcursor_get_bigint(NULL));
// move the subcursor in use to next position within the result subset (i.e. second position)
hdfql_subcursor_next(NULL);
// display current element of the subcursor in use as a long long (should be "Current element of subcursor is 2")
printf("Current element of subcursor is %lld\n", *hdfql_subcursor_get_bigint(NULL));