Oracle Database Lite Sequences negative

Question

Hi,
What might explain why negative OLITE assigned sequences?
I do not understand the documentation.
Regards

Answer 1

Where did you get these values from?
in the repository database the sequence definition is stored in table c$all_sequences and has a name, id value, min_value, threshold, window size, increment by and mode (which should be NA_SEQ rather than OA_SEQ).
In the range for each user (table c$seq_clients) the data is user name, current value, min_value and max_value
from the client side the table all_sequences has sequence owner, name, min_value (updated to record current value) and max_value - no mode or threshold
It is not a good idea to start sequence ranges at 0, as this is the first value that will be assigned, start the range with 1. unless you have a specific reason, increment by 2 is not necessary, and will cause the sequence range to be used quite quickly. using this definition, the sequence range for any user will refresh after 25 inserts, and will leave on average large gaps in the values created from the sequence (for example, the effect of this definition would be to allocate numbers 1 to 200 to a user, user makes 25 inserts and range is refreshed - even numbers 2 to 26 not used, neither are 27-200, you have only used 25 values out of a possible 200 (12.5%) - not very efficient). the size of the gap between the threshold and the max value depends on your user needs, but a large gap is where you expect users not to synchronise regularly and therefore overflow the threshold value before they sync. If this is the case i would advise setting a higher max value.
sequences defined in oracle lite are also distinct from thiose on the server. If the sequence is used for populating PK values on a table, and this table is added to by both the clients and the server, then i would advise creating sequences with a high start value to prevent overlaps - this is the case in our application and the oracle lite sequences are defined to start with a value of 100,000,000 and a window of 1,000,000