Developer Documentation Library > Data Model > Available DSCs > SPSS Statistics SAV DSC > Reading from an SPSS Statistics .sav file > Variable definitions when reading from a .sav file > IBM SPSS Statistics date variables
 
IBM SPSS Statistics date variables
The SPSS Statistics SAV DSC maps IBM SPSS Statistics date variables to MDM date variables. The following table describes how the converts the IBM SPSS Statistics variable's value to the MDM date variable's value, depending on the format of the IBM SPSS Statistics variable:
Format of IBM SPSS Statistics variable
Method of conversion
TIME and DTIME.
The IBM SPSS Statistics value, which represents a time interval measured in seconds, is divided by 86400.0. This converts it from a (positive or negative) count of seconds to a count of days, (including fractional days), which is the basis of date representation in SQL. If displayed in the MDM, this will appear as the base date 1899-12-30 00:00:00 plus the offset. For example, the value 8640999.0, displayed in IBM SPSS Statistics as a TIME of 2400:16:39 or a DTIME of 100 00:16:39 will be converted to 100.0115625, appearing in the MDM as 1900-04-09 00:16:39.
WKDAY when the value is 1 to 7, and MONTH when the value is 1 to 12.
The IBM SPSS Statistics value, which is one of a predefined set of values, is preserved unchanged. For example, a WKDAY of 1.0 (MONDAY) is represented in the MDM by 1.0 (1900-01-01 00:00:00). A MONTH value of 3.0 (MARCH) is represented in the MDM by 3.0 (1900-01-03 00:00:00). For both WKDAY and MONTH types, any fractional part of the value will be preserved by the MDM and used to indicate the time of day.
WKDAY and MONTH when the value is large, and DATE, DATETIME, ADATE, JDATE, MOYR, QYR, WKYR, EDATE, and SDATE.
The IBM SPSS Statistics value represents a particular instant in time. A non-negative floating-point value is converted to the SQL representation of that time. Any negative value (except system-missing) is converted to -115859.0 (1582-10-14 00:00:00, corresponding to 0.0 in IBM SPSS Statistics). Dates before 1582-10-14 00:00:00 are not supported.
See also
Variable definitions when reading from a .sav file