Management of temporal data by means of a canonical schema

A computer program for managing at least one bitemporal table that contains at least one row that contains a temporal foreign key, embodied in a computer-readable storage medium, the computer program comprising:

• logic adapted to distinguish at least one episode, the at least one episode comprising an effective-time initial row in the at least one bitemporal table and a group of zero or more other rows in the at least one bitemporal table;
• and
• logic adapted to assign an effective-time period to the at least one episode, wherein the effective-time period is the logical union of the effective-time initial row's effective-time period and the zero or more other rows' effective-time periods;
• wherein the effective-time initial row and the zero or more other rows represent the same object in a common assertion-time period.

A computer program for managing at least one table having an assertion-time period, embodied in a computer-readable storage medium, the computer program comprising:

• logic adapted to utilize a column in the table, wherein the column contains one or more values indicating that the row has an assertion-time period that is entirely in the past, and one or more values indicating that the row does not have an assertion-time period that is in entirely the past;
• logic adapted to set the column, on all rows created by temporal transactions, to a first value that indicates that the row does not have an assertion-time period that is entirely in the past;
• and
• logic adapted to set the column, on all rows moved into past assertion time by means of temporal transactions, to a second value that indicates that the row does have an assertion-time period that is entirely in the past.

A computer program for managing at least one table having an effective-time period, embodied in a computer-readable storage medium, the computer program comprising:

• logic adapted to utilize a column in the table, wherein the column contains one or more values indicating that the row has an effective-time period that is entirely in the past, and one or more values indicating that the row does not have an effective-time period that is entirely in the past;
• logic adapted to set the column to a first value indicating that the row has an effective-time period that is entirely in the past, on all rows created by temporal transactions that specify effective-time periods that are entirely in the past;
• and
• logic adapted to set the column to a second value indicating that the row does not have an effective-time period that is entirely in the past, on all rows created by means of temporal transactions that specify or accept as default values effective-time periods that are not in entirely the past.