he problem was created years ago when systems were first developed; most likely because of a demand to save disk space. You see, it takes two less bytes of disk space to store the data in the YYMMDD format than it does to store data in the CCYYMMDD format.
This method of storing the data was seemingly justified, as the first generation of developers didn’t think their software would be around for the length of time that it has. (They thought new replacement software would be developed by the year 2000, and therefore it wouldn’t be a problem.) They were wrong.
The problem is trivial for someone looking at a date on a report or a display device; as they will understand that the year 00 follows the year 99. Computers however, aren’t nearly as understanding as humans. When computers go to sort numerical information in a date sequence, the transaction will not process as we expect, because 00 is, after all, less than 99. For programs using logic which demands that start dates be less than end dates, there will definitely be a problem.
Just imagine starting a five year housing mortgage, beginning in 1997 and ending in 2002. The actual difference of 5 years becomes non-logical and unacceptable to a computer which is programmed to interpret the term as 97 subtracted from 02, or negative 95 years! In essence, as with this case in point, the problem of time suspension has the potential (depending on how dates are used in your applications), to stop you from carrying on business.
Because of the number of computers that will need to be converted and the limited number of people available to do conversions, a company is well advised to get on with this before the rush. When making your plans, look for an application development partner that doesn’t believe in scare tactics; but rather, approaches the problem as “Let’s get the job done. We know how. We’re good at it and we’re ready.”
There are three areas to be addressed by every company facing the year 2000 problem:
Computer problems are not only firmware, but also relate to capacity. The firmware problem is up tp IBM to solve, but most companies have not thought about the implications of conversion testing -- a process which must take place simultaneously with day-to-day operations. It is obvious that any tests must be carried out in a separate environment from operations – if only to safeguard the operating databases. In theory, this means that every company will have to hire a separate test machine for the conversion project, and this may not be easily possible in the time scale.
Many companies still use systems which were developed several years ago. Generally these systems were poorly documented and it is more than likely that the original development staff have since moved on. Even those companies who use third party software will have created some sort of interface between packages or tailored the system to meet specific needs. The first function of every conversion therefore is to identify those programs which need modifying. Once this is done, developers have to change every program that uses two digit year fields and write the programs to convert legacy date fields into true dates.
Most companies have information which is several years old. Some have very old data which may relate to dates which are 60 or 70 years old, particularly in the insurance market. As a result, companies may be unable to make assumptions on the meaning of legacy dates, without careful consideration of the meaning of each date field. A complete set of database update programs will need to be generated (normally one per database file to be updated) to add the century to every converted date field within the system. Furthermore, complete data sets of historical data running into the next millennium will need to be constructed so as to permit final acceptance testing on millennium data.
The year 2000 is a real deadline. There is no way a company can avoid a conversion project and stay in business. However there is no reason why AS/400 users could not achieve their goals, if they get an early start, and partner with the appropriate expertise in this field.