For most databases there is a mechanism to update a character string of “0” length into a VARCHAR column. Connect CDC can identify that a character string is “0” length, and the Applier can update a “0” length string into a target database.
However, for Teradata, there is no mechanism when writing the data file, that the Applier can use to differentiate between a value with “0” length and a NULL value. To differentiate between these 2 values, the Applier checks for a character value which has a length of “0”, and then, in this situation, loads 1 space.