What is Maxrecursion SQL Server?
The MAXRECURSION value specifies the number of times that the CTE can recur before throwing an error and terminating. You can provide the MAXRECURSION hint with any value between 0 and 32,767 within your T-SQL query, with MAXRECURSION value equal to 0 means that no limit is applied to the recursion level.
Can you use recursion in SQL?
Recursion is achieved by WITH statement, in SQL jargon called Common Table Expression (CTE). It allows to name the result and reference it within other queries sometime later.
How do you set Maxrecursion on CTE?
Example
- DECLARE @Min int;
- DECLARE @Max int;
- SET @Max = 150;
- SET @Min = 1;
- WITH Sequence_ AS(SELECT @Min AS num UNION ALL SELECT num + 1 FROM Sequence_ WHERE num + 1 <= @Max)
- SELECT num FROM Sequence_
- OPTION(MAXRECURSION 200)
How do you write a recursive query in SQL Server?
First, execute the anchor member to form the base result set (R0), use this result for the next iteration. Second, execute the recursive member with the input result set from the previous iteration (Ri-1) and return a sub-result set (Ri) until the termination condition is met. Third, combine all result sets R0, R1, …
Can we join two CTE?
But Can I Use One CTE Inside Another CTE? A straightforward question deserves a straightforward answer: yes, you can. Now that you know how to use multiple CTEs, writing a CTE that references another CTE is just a variation of what you’ve learned.
How do I create a hierarchy query in SQL Server?
- Identify the Anchor and Recursive Query.
- Add the Anchor and Recursive query to a CTE.
- Add an expression to track hierarchical level.
- Add a self-referencing INNER JOIN statement.
How does CTE work in SQL Server?
Specifies a temporary named result set, known as a common table expression (CTE). This is derived from a simple query and defined within the execution scope of a single SELECT, INSERT, UPDATE, DELETE or MERGE statement. This clause can also be used in a CREATE VIEW statement as part of its defining SELECT statement.
What is difference between CTE and temp table?
This biggest difference is that a CTE can only be used in the current query scope whereas a temporary table or table variable can exist for the entire duration of the session allowing you to perform many different DML operations against them.