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#include <grass/vector.h>
#include <grass/dbmi.h>
#include <grass/glocale.h>
/* get height for DB
returns 0 on success -1 on failure
*/
int get_height(const struct field_info *Fi, const char *hcolumn,
dbDriver *driver, int cat, double *height)
{
int more;
double objheight;
char query[DB_SQL_MAX];
dbString sql;
dbCursor cursor;
dbTable *table;
dbColumn *column;
dbValue *value;
db_init_string(&sql);
sprintf(query, "SELECT %s FROM %s WHERE %s = %d", hcolumn, Fi->table,
Fi->key, cat);
G_debug(3, "SQL: %s", query);
db_set_string(&sql, query);
if (db_open_select_cursor(driver, &sql, &cursor, DB_SEQUENTIAL) != DB_OK)
G_fatal_error(_("Unable to select attributes category %d"), cat);
table = db_get_cursor_table(&cursor);
column = db_get_table_column(table, 0); /* first column */
if (db_fetch(&cursor, DB_NEXT, &more) != DB_OK)
return -1;
value = db_get_column_value(column);
G_debug(3, "column_host_type: %d", db_get_column_host_type(column));
objheight = db_get_value_as_double(value, DB_C_TYPE_DOUBLE);
G_debug(3, "height from DB: %f", objheight);
*height = objheight;
return 0;
}
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