GetLevel (Database Engine)

THIS TOPIC APPLIES TO:yesSQL Server (starting with 2008)yesAzure SQL DatabasenoAzure SQL Data Warehouse noParallel Data Warehouse

Returns an integer that represents the depth of the node this in the tree.

Syntax


-- Transact-SQL syntax  
node.GetLevel ( )   

-- CLR syntax  
SqlInt16 GetLevel ( )   

Return Types

SQL Server return type:smallint

CLR return type:SqlInt16

Remarks

Used to determine the level of one or more nodes or to filter the nodes to members of a specified level. The root of the hierarchy is level 0.

GetLevel is very useful for breadth-first search indexes. For more information, see Hierarchical Data (SQL Server).

Examples

A. Returning the hierarchy level as a column

The following example returns a text representation of the hierarchyid, and then the hierarchy level as the EmpLevel column for all rows in the table:

SELECT OrgNode.ToString() AS Text_OrgNode,   
OrgNode.GetLevel() AS EmpLevel, *  
FROM HumanResources.EmployeeDemo;  

B. Returning all members of a hierarchy level

The following example returns all rows in the table at the hierarchy level 2:

SELECT OrgNode.ToString() AS Text_OrgNode,   
OrgNode.GetLevel() AS EmpLevel, *  
FROM HumanResources.EmployeeDemo  
WHERE OrgNode.GetLevel() = 2;  

C. Returning the root of the hierarchy

The following example returns the root of the hierarchy level:

SELECT OrgNode.ToString() AS Text_OrgNode,   
OrgNode.GetLevel() AS EmpLevel, *  
FROM HumanResources.EmployeeDemo  
WHERE OrgNode.GetLevel() = 0;  

D. CLR example

The following code snippet calls the GetLevel() method:

this.GetLevel()  

See Also

hierarchyid Data Type Method Reference
Hierarchical Data (SQL Server)
hierarchyid (Transact-SQL)