Resources for IT Learners and Leaders

All the data that is found on earth is significantly to drive all the organizations in the world, whether a small business or large enterprises. Big data refers to that data which structured as well as unstructured and it has been estimated that more than 80% of the data is still unstructured. It is not surprising because we are expanding and developing at a very fast pace which results in the avalanche of data.

Identity columns are nothing new in T-SQL.  They are great when you want a unique number to be automatically assigned every time you insert a new record.  The trouble is that while they are unique within the table, they are probably the same between tables.  Every table with an identity column has a 1 for the first record, a 2 for the second, etc.  Of course you can set the seed and increment for the identity column to something other than (1,1), but you still have to manually track which table has which seed.  Trying to track that is destined for failure.  What we really need is a way to have automatically assigned numbers for new records, but ones which are guaranteed to be unique across any table that uses them.  Of course, you know I wouldn’t be writing this if there weren’t a solution.  In SQL Server 2012, Microsoft introduced something called the SEQUENCE object that does this very thing.