Updating identity column sql server 2016

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Suppose you have a table with a large amount of data without an identity column and you want to add an IDENTITY property to the existing column. Consider the following dataset: create table testing (id int not null, value decimal(12,2)) insert into testing(id,value) select 1,rand()*10000 union all select 2,rand()*10000 union all select 3,rand()*10000 union all select 4,rand()*10000 union all select 5,rand()*10000 Now the table testing1 will have data with identity values and just like with Method 1, you can use this identity column for any reference.It is important to note that in SQL Server you cannot alter a column to have an identity property. Method 3: Use ALTER TABLE SWITCH option Create a new table with the same schema as that of the table Now the table testing has an IDENTITY column with all the data.He now has good level of knowledge in SQLServer, Oracle, My SQL and Postgre SQL as well.He is also one of the leading posters at a moderator at Method 3 is very fast as it switches the partition from one table to another very quickly.So this method will take only few seconds compared to the other two methods.

If your original NVARCHAR column has a COLLATION property (for example, case-sensitivity or Japanese language), the index is organized according to the language rules or the case sensitivity rules associated with the NVARCHAR column.Now the question is "which method is the best to use?" Well, Methods 1 and 2 may be time consuming if the source table has millions of rows.He started his career as a developer working with Visual Basic 6.0, SQL Server 2000 and Crystal Report 8.As years went by, he started working more on writing queries in SQL Server.

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