PARSENAME string using function and taken into a standard format IPv4

MS SQL server has a function PARSENAME ( 'object_name', object_piece) .

Function has two parameters:

Object_name

Object name search. That is: the name of the database server name the owner of the object name.

Object_piece

Is the type of object retrieval. A value of 1 to 4.

 

For example, to store incoming custom function or procedure table name: the TABLE_CATALOG . The TABLE_SCHEMA . . TABLE_NAME COLUMN_NAME dynamic operation of the data table.

 

For columns:

 

 

DECLARE @str  NVARCHAR(MAX) = N'testdb.dbo.table_part.qty'

SELECT 
PARSENAME(@str,4) AS [TABLE_CATALOG],
PARSENAME(@str,3) AS [TABLE_SCHEMA],
PARSENAME(@str,2) AS [TABLE_NAME],
PARSENAME(@str,1) AS [COLUMN_NAME]
GO

Source Code

 

 Another presentation, the definition of a table variable to store some random add IP address:

 

 

 Then SELECT table, and use the ORDER BY sort:

 

 

This sort result is not what we want, it's just the size for each period of the first digital sort.

This is why, because these IP address, not a standard IP address.

The IP address is converted to IP standard, refer to this " converted to standard IPv4 format " https://www.cnblogs.com/insus/p/10958864.html

The above function, there are used PARSENAME line processing function.

 

 

 

;WITH cte_ips AS
(
    SELECT [IPv4],[dbo].[svf_ConvertToStandardIPv4]([IPv4]) AS [std_ip] FROM @ips
)
SELECT [IPv4],[std_ip] FROM cte_ips
ORDER BY PARSENAME([std_ip],4),
         PARSENAME([std_ip],3),
         PARSENAME([std_ip],2),
         PARSENAME([std_ip],1)

Source Code