I m writing a new asp net core web api and one of my requirements is to be able to leverage ef core 3 1 to grab the next value of a sequence defined in my sql server as the id for a record i need to store. To achieve this i needed one table but now i want to convert it to a sequence object will it give any advantage.
Oracle uses the concept of sequence to create numerical primary key values as we add rows of data into a table.
How to get next value of sequence in sql server. I want to get the current value from my sequence the same value that is shown in the sequence properties window sql server management studio. Sql server all supported versions azure sql database generates a sequence number from the specified sequence object. Sql advanced sql sequence and nextval.
In current scenario i m doing something related by increment by one in stored procedure previous value stored in one table and passing that value to c code. Now that you ve created a sequence object to simulate an autonumber field we ll cover how to retrieve a value from this sequence object. For a complete discussion of both creating and using sequences see sequence numbers.
This would retrieve the next value from contacts seq. Public int getnextsequencevalue var rawquery database sqlquery. You must qualify nextval or currval with the name or synonym of a sequence object that exists in the same database using the format sequence nextval or sequence currval an expression can also qualify sequence by the owner name as in zelaine myseq currval.
Try putting next value for as an argument to the function. The next value for function can be used as the default value for a column in a table definition. I m struggling to find a way to do this in ef 6 x i used a method directly on the dbcontext descendant like this.
Use sp sequence get range to get a range of multiple sequence numbers at once. A sequence can be defined as any integer data type. The sequence number is allocated when next value for is called even if the number is never inserted into a table.
You can access the value of a sequence using the nextval or currval operators in sql statements. Use sp sequence get range to generate reserve a range of sequence numbers. Create sequence ordernumbersequence as int start with 4000 increment by 1 minvalue 0 no maxvalue no cache.
That or back to the drawingboard. I know how to create sequence and get next value in sql server. Select next value for contacts seq.
I m trying to call sequence object inside sql server user defined function. Whereas numerical primary key population for mysql and sql server is tied to individual tables in oracle the sequence construct is created separately and is not tied to an individual table. You cannot have it in the function because a function is not permitted to change database state.
To retrieve the next value in the sequence order you need to use the next value for command. My sequence is created with this statement.