The behavior of the bool, char, bit, and varbit data types for statistics functions is:
- For character columns, the values can contain "", "NA", or an all digit string. For example, "123".
- For boolean columns, the Aster boolean is:
- converted to 1 or 0 (numeric) through RODBC
- converted to "t" or "f" through ta.pull
- converted to "t" or "f" in the STREAM Rexec call
- For bit and varbit columns, the values only contain "1" and "0".
In each case, RODBC will recognize the data type value as a numeric (double or integer) values. As a result, statistics functions do not detect non-numeric columns before executing the SQL.