SQL Server 2012 column identity increment jumping from 6 to 1000+ on 7th entry
I have a strange scenario in which the auto identity int column in my SQL Server 2012 database is not incrementing properly.
Say I have a table which uses an int auto identity as a primary key it is sporadically skipping increments, for example:
1, 2, 3, 4, 5, 1004, 1005
This is happening on a random number of tables at very random times, can not replicate it to find any trends.
How is this happening? Is there a way to make it stop?
Answer
This is all perfectly normal. Microsoft added sequences in SQL Server 2012, finally, i might add and changed the way identity keys are generated. Have a look here for some explanation.
If you want to have the old behaviour, you can:
- use trace flag 272 - this will cause a log record to be generated for each generated identity value. The performance of identity generation may be impacted by turning on this trace flag.
- use a sequence generator with the NO CACHE setting (http://msdn.microsoft.com/en-us/library/ff878091.aspx)