ToString (Database Engine)

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

Returns a string with the logical representation of this. ToString is called implicitly when a conversion from hierarchyid to a string type occurs. Acts as the opposite of Parse (Database Engine).


-- Transact-SQL syntax  
node.ToString  ( )   
-- This is functionally equivalent to the following syntax  
-- which implicitly calls ToString():  
CAST(node AS nvarchar(4000))  
-- CLR syntax  
string ToString  ( )   

Return types

SQL Server return type:nvarchar(4000)

CLR return type:String


Returns the logical location in the hierarchy. For example, /2/1/ represents the fourth row ( Microsoft SQL Server) in the following hierarchical structure of a file system:

/        C:\  
/1/      C:\Database Files  
/2/      C:\Program Files  
/2/1/    C:\Program Files\Microsoft SQL Server  
/2/2/    C:\Program Files\Microsoft Visual Studio  
/3/      C:\Windows  


A. Transact-SQL example in a table

The following example returns both the OrgNode column as both the hierarchyid data type and in the more readable string format:

SELECT OrgNode,  
OrgNode.ToString() AS Node  
FROM HumanResources.EmployeeDemo  
ORDER BY OrgNode ;  

Here is the result set.

OrgNode   Node  
0x        /  
0x58      /1/  
0x5AC0    /1/1/  
0x5B40    /1/2/  
0x5BC0    /1/3/  
0x5C20    /1/4/  

B. Converting Transact-SQL values without a table

The following code example uses ToString to convert a hierarchyid value to a string, and Parse to convert a string value to a hierarchyid.

DECLARE @StringValue AS nvarchar(4000), @hierarchyidValue AS hierarchyid  
SET @StringValue = '/1/1/3/'  
SET @hierarchyidValue = 0x5ADE  

SELECT hierarchyid::Parse(@StringValue) AS hierarchyidRepresentation,  
@hierarchyidValue.ToString() AS StringRepresentation ;

Here is the result set.

hierarchyidRepresentation StringRepresentation

------------------------- -----------------------

0x5ADE /1/1/3/

C. CLR example

The following code snippet calls the ToString() method:


See also

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