The P00IO is related to the number of records that can be read at one time during an inquiry and this can be user defined …with limits.
UDC Table 00/IO holds program numbers and a value for the number of records that can be “read” during the inquiry. So you may think that making this number as big a value as the field will hold would be a good, one time solution to prevent the P00IO from disrupting your future inquiries. Well, it is not that simple. Each program has coding to set the maximum usable digits that can be set in the UDC and if exceeded, the value you enter could be seen by the system as zero.
Here is an example. If you update UDC 00/IO with a value of 100,000 for a program that has a maximum usable digits value of 5, 100,000 will actually be seen as zero. This is due to truncating 100,000 from the LEFT to reduce the number of digits to the number defined in the program. In this example, the 6 digit ‘100,000’ value will be reduced by dropping the 1, resulting in ‘00,000’ so the P00IO will be presented for any inquiry in that program. In contrast, if you used 999,999 for the same program, this 6 digit value would drop the left most “9” resulting in a value of 99,999 so the inquiry should produce better results.
So prior to adding new programs to or adjusting existing values in UDC 00/IO, you need to know the maximum usable digits for that program. IO Limit Exceeded Due to Excessive Amount of Records F5 F6 (Doc ID 827483.1) provides details related to how you can search the program code to find the maximum usable digits for the program you are using. Having this information so the program can be properly defined will help you to avoid the P00IO window from popping up in your future inquiries.