The UNICOM Intelligence Data File CDSC adds a column to the corresponding Ln table for each Metadata Model (MDM) variable that exists at that level of the hierarchy. The column name is constructed from the MDM variable name and a suffix that indicates the MDM variable type.

The following table shows how the UNICOM Intelligence Data File CDSC maps MDM variable types to UNICOM Intelligence Data File schema types:

For all non-categorical MDM variable types, if the response to the MDM variable is a null value, the UNICOM Intelligence Data File CDSC writes a null value to the corresponding column.

MDM categorical variables, whether single-response or multiple response, are stored either as a multiple category set or as a string. The format used is determined by the value of the variable's EffectiveMaxValue property and the value of the MaxMultiCol custom connection property (see Custom connection properties used by the UNICOM Intelligence Data File CDSC.

The category set consists of one or more integer columns. The number of columns added to the table equals the value of the MDM variable's EffectiveMaxValue property (which is 1 for single-response categorical variables). The first category in the response is written to the first column in the set, the second category in the response is written to the second column in the set, and so on. If the response contains less categories than there are columns in the set, the UNICOM Intelligence Data File CDSC writes null values to the unused columns. The column name suffix is :Cn, where n is 1 for the first column in the set, 2 for the second column, and so on.

If the response is an empty categorical response, the UNICOM Intelligence Data File CDSC writes 0 to the first column in the set. If the response is a null value, the UNICOM Intelligence Data File CDSC writes –1 to the first column in the set. If the response contains more categories than there are integer columns to store the response, the action taken by the UNICOM Intelligence Data File CDSC depends on the value of the MR Init Allow Dirty connection property (see Connection properties). If the value of MR Init Allow Dirty is False, the UNICOM Intelligence Data File CDSC stops and issues an error message. If the value of MR Init Allow Dirty is True, the UNICOM Intelligence Data File CDSC silently discards the excess categories in the response.

The categorical response is stored in a single text column. The string contains the MDM mapped category values in the order that they appear in the response, delimited by semicolons. The column name suffix is :S. If the response is an empty categorical response, the UNICOM Intelligence Data File CDSC writes a zero-length string to the column. If the response is a null value, the UNICOM Intelligence Data File CDSC writes a null value to the column.