Get Server name, Database name, Schema name or Object name

There is a simple T-SQL function that Returns the specified part of an object name. using this function we can retrieve object name, owner name, database name, and server name from a fully qualified object name. This function doesn't require the object name that is provided is in the database, its only returns the specified part of the specified object name.

PARSENAME ( 'object_name' , object_piece )

object_piece

Object_piece is the part that you want to retrieve.
1 = Object name 
2 = Schema name
3 = Database name
4 = Server name

what this function actually doing is, it getting the object name and split the object name by period (‘.’) and returning the specified position in Object_piece.

SELECT PARSENAME('ServerName.DatabaseName.SchemaName.ObjectName',1) AS ObjectName
      ,PARSENAME('ServerName.DatabaseName.SchemaName.ObjectName',2) AS SchemaName
      ,PARSENAME('ServerName.DatabaseName.SchemaName.ObjectName',3) AS DatabaseName
      ,PARSENAME('ServerName.DatabaseName.SchemaName.ObjectName',4) AS ServerName

if you smart enough you can use this for many things, such as separating extension from the file name or parse an IP address. Just remember you are working backwards.

How to add line break to a string

when we creating dynamic sql it is easy to read or troubleshoot the SQL query if we format it. I’m always adding line breaks to my dynamic queries using following code.
Here I’m just declaring a variable and setting the CR and line breaks to it. you can use one of these CHAR(13) for CR and CHAR(10) is for DOS/Windows style CRLF Line breaks.

DECLARE @line_break NVARCHAR(2);
SET @line_break = CHAR(13) + CHAR(10);

PRINT '-------------------------'+@line_break+'Line 1' + @line_break + 'Line 2' + @line_break +'-------------------------'

result…
-------------------------
Line 1
Line 2
-------------------------

How to monitor page split in SQL Server

I had a question when creating or rebuilding a index, the fillfactor value that I set to it is the perfect value for my requirement. I have found a query that use a undocumented function and read the transaction log and identify the indexes that are splitting.



SELECT AllocUnitName,COUNT([AllocUnitName]) [Splits]
FROM ::FN_DBLOG(NULL,NULL)
WHERE Operation=N'LOP_DELETE_SPLIT' AND PARSENAME(AllocUnitName,3)<>'sys'
GROUP BY AllocUnitName




there is another way to find the page split with Extended events. for more details go to Michael Zilberstein's Blog

Disable constraints on a table

Sometimes it's useful to disable one or more constraints on a table, do something significant, and then re-enable the constraints after you're done. This is most often done to improve performance during a bulk load operation, Some type of Database cleanup process.

How to: Enable/Disable single constraint

According to SQL Server Books Online, we can disable constraints using the ALTER TABLE statement. for more details go to ALTER TABLE (Transact-SQL)

for an example:

/***** disable the FK_TABLE2_TABLE1 constraint on TABLE2 *****/

ALTER TABLE dbo.TABLE2 NOCHECK CONSTRAINT FK_TABLE2_TABLE1

/***** enable the FK_TABLE2_TABLE1 constraint on TABLE2 *****/

ALTER TABLE dbo.TABLE2 CHECK CONSTRAINT FK_TABLE2_TABLE1

How to: Enable/Disable all constraint

The following example shows how to disable all constraints on a table.
here i'm creating T-SQL statement for all tables using INFORMATION_SCHEMA View and execute them

--Disable
DECLARE @SQL VARCHAR(MAX) 
SELECT @SQL = ISNULL(@SQL,'') + 'ALTER TABLE ' + QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME) + ' NOCHECK CONSTRAINT ALL;' 
FROM INFORMATION_SCHEMA.Tables 
WHERE TABLE_TYPE = 'BASE TABLE' 
EXEC(@SQL) 
go 

--Enable 
DECLARE @SQL VARCHAR(MAX)
SELECT @SQL = ISNULL(@SQL,'') + 'ALTER TABLE ' + QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME) + ' CHECK CONSTRAINT ALL;' 
FROM INFORMATION_SCHEMA.Tables 
WHERE TABLE_TYPE = 'BASE TABLE' 
EXEC(@SQL)