rollback
Execute the SQL ROLLBACK WORK statement.
Available in:
| Apps (win) | Apps (char) | Reportwriter | RPC | Standalone PL | 
| X | X | X | X | X | 
Syntax
void rollback([update])
keyword      update
Description
| update | (optional) specifies that the transaction is for update.
The default (unspecified) is read-only. | 
Notes
Some database systems do not provide the capability of specifying
read-only or update transactions. On these systems, option update is ignored.
See also commit().
Example
Deletes rows in a table and confirm it with the user before committing
the work.
{
int n_rows;
n_rows = exec_sql("DELETE FROM staff WHERE id = 20");
if (n_rows > 0) {
  printf("You are about to delete" ^^ to_char(n_rows) ^^ "rows");
  if (prompt("Proceed (Y/N) ==> ") == "Y") commit();
  else rollback();
 }
}