How to increase the size of a database (Enterprise Manager)

How to increase the size of a database (Enterprise Manager)

To increase the size of a database

Expand a server group, and then expand a server.

Expand Databases, right-click the database to increase, and then click Properties.

To increase the data space, click the General tab. To increase the transaction log space, click the Transaction Log tab.

To add a new file, click the next empty row and, in the File name column, enter the file name that will contain the additional space.

The file location is generated automatically and given the .ndf suffix for a database file, or an .ldf suffix for a transaction log file.

To change the default values provided in the File name, Location, Space allocated (MB), and Filegroup (not applicable for the transaction log) columns, click the cell to change and enter the new value.

For existing files, only the Space allocated (MB) value can be changed; the new value must be larger than the existing value.

To specify how the file should grow, select from these options:

To allow the currently selected file to grow as more data space is needed, select Automatically grow file.

To specify that the file should grow by fixed increments, select In megabytes and specify a value.

To specify that the file should grow by a percentage of the current file size, select By percent and specify a value.

To specify the file size limit, select from these options:

To allow the file to grow as much as necessary, select Unrestricted filegrowth.

To specify the maximum size to which the file should be allowed to grow, select Restrict filegrowth (MB) and specify a value.

Note  The maximum database size is determined by the amount of disk space available and the licensing limits determined by the version of SQL Server you are using.

How to Get Available space on Database

How to Get Available space on Database using a Dynamic Query:-

EXEC(N'USE ' + @dbname + N' select  [FILE_SIZE_MB] =

           convert(decimal(12,2),round(size/128.000,2)),

     [SPACE_USED_MB] =

           convert(decimal(12,2),round(fileproperty(name,''SpaceUsed'')/

128.000,2)),

     [FREE_SPACE_MB] =

           convert(decimal(12,2),round((size-

fileproperty(name,''SpaceUsed''))/128.000,2)),

     [DEVICE_NAME] = left(NAME,15)

from  dbo.sysfiles;')

Minus Keyword in SQL Server 2000

Minus Keyword in SQL Server 2000
Oracle supports "Minus" Keyword, but today suddenly when i tried to execute same in SQL Server it won't work. So, here is an alternate way to use "Minus" in SQL Server:-
Example:
Select City, Statefrom Employee Minus Select City, State from Customer
This will work fine with Oracle, but won't work with SQL Server. So alternate way to use "Minus" Keyword in SQL Server:-
Select City, Statefrom Employee Except Select City, State from Customer

Create A Comma Delimited List From a Column

Create A Comma Delimited List From a Column

Create Sample Data for Both Solutions

-- Suppress data loading messages SET NOCOUNT ON   -- Create Sample Data  CREATE TABLE TeamInfo    (  MemberID    int IDENTITY,       TeamID      int,        FirstName   varchar(50)    )   -- Load Sample Data INSERT INTO TeamInfo VALUES ( 1, 'Jim' ) INSERT INTO TeamInfo VALUES ( 1, 'Mary' ) INSERT INTO TeamInfo VALUES ( 1, 'Bob' ) INSERT INTO TeamInfo VALUES ( 2, 'Sue' ) INSERT INTO TeamInfo VALUES ( 2, 'Ralph' ) INSERT INTO TeamInfo VALUES ( 2, 'Ellen' ) INSERT INTO TeamInfo VALUES ( 3, 'Bill' ) INSERT INTO TeamInfo VALUES ( 3, 'Linda' )

create function -- SQL 2000, Retrieve desired data

-- With SQL 2000, we will create a User Defined Function to do the concatenation. -- While this solution can also be used with SQL Server 2005/SQL Server 2008,  -- the previous suggestion is more efficient.   CREATE FUNCTION dbo.fnMakeTeamList    (  @TeamID int  )    RETURNS varchar(1000) AS    BEGIN       DECLARE @TempTeam table          (  Firstname varchar(20)  )       DECLARE @TeamList varchar(1000)       SET @TeamList = ''       INSERT INTO @TempTeam          SELECT FirstName          FROM TeamInfo          WHERE TeamID = @TeamID       IF @@ROWCOUNT > 0          UPDATE @TempTeam             SET @TeamList = ( @TeamList + FirstName + ', ' )       RETURN substring( @TeamList, 1, ( len( @TeamList ) - 1 ))    END   -- Usage SELECT     TeamID,     MemberList = dbo.fnMakeTeamList( TeamId )  FROM TeamInfo  GROUP BY TeamID   -- Results TeamID     MemberList 1 Jim, Mary, Bob 2 Sue, Ralph, Ellen 3 Bill, LindaS

QL Server 2005 / SQL Server 2008 Solution

--Retrieve desired data SELECT    t1.TeamID,    MemberList = substring((SELECT ( ', ' + FirstName )                            FROM TeamInfo t2                            WHERE t1.TeamID = t2.TeamID                            ORDER BY                                TeamID,                               FirstName                            FOR XML PATH( '' )                           ), 3, 1000 )FROM TeamInfo t1 GROUP BY TeamID   -- Results TeamID     MemberList 1 Bob, Jim, Mary 2 Ellen, Ralph, Sue 3 Bill, Linda

ISNULL() and COALESCE()

ISNULL() and COALESCE()

In dealing with NULL values in SQL Server, the developer is often faced with the requirement to evaluate the content of a field, and when said field in null, return another value (or field). There are two functions in SQL Server which support this requirement: ISNULL() and COALESCE.()

ISNULL() accepts two parameters. The first is evaluated, and if the value is null, the second value is returned (regardless of whether or not it is null). The following queries will return the second parameter in both cases:

SELECT ISNULL(NULL, 1) --Returns 1 SELECT ISNULL(NULL, NULL) --Returns NULL 

COALESCE()

COALESCE() is a TSQL function which, like ISNULL, is built into SQL Server. Unlike ISNULL, COALESCE is also a part of the ANSI-92 SQL Standard. Coalesce returns the first non-null expression in a list of expressions. The list can contain two or more items, and each item can be of a different data type. The following are valid examples of COALESCE:

SELECT COALESCE(NULL, 1) --Returns 1   SELECT COALESCE(NULL, 3, NULL, 1) --Returns 3 

ISNULL vs. COALESCE

Whenever multiple methods exist for addressing a single problem, the inevitable question is: which method is better? There are a few differences between the two functions which make COALESCE come out on top more often than not:
- COALESCE is ANSI-92 compliant. In the event that you need to port your code to another RDBMS, COALESCE will not require rework.
- COALESCE accepts greater than two expressions, whereas ISNULL accepts only two. In order to compare three expressions with ISNULL, you would have to nest expressions:
SELECT ISNULL(ISNULL(Col1, Col2), Col3)
- ISNULL constrains the result of a comparison of parameterrs to the datatype of the first value. For example, the following query will produce some often undesirable results using ISNULL, however it will behave as expected with COALESCE:

DECLARE @Field1 char(3), @Field2 char(50) SET @Field2 = 'Some Long String'   SELECT ISNULL(@Field1, @Field2) --Returns 'Som' SELECT COALESCE(@Field1, @Field2) --Returns 'Some Long String' 

Note: In other situations, COALESCE will produce unexpected results. COALESCE by nature promotes it's arguments to the highest datatype among compatable arguments (arguments which are not explicitly case, and which aren't compatable, will of course throw an error). When using COALESCE on an integer and a datetime, in that order, COALESCE will cast the integer as a datetime. For example:
SELECT COALESCE(5, GETDATE())
Will not return 5, it will return 1900-01-06 00:00:00.000 (5 as a datetime).

Performance

For most purposes, ISNULL and COALESCE perform in an almost identical fashion. It is generally accepted that ISNULL is slightly quicker than COALESCE, but not sufficiently to outweigh it's inherent limitations. As with any performance related issue, if performance is a significant concern, write it both ways, and test!

SQL2008: Lock a Stored Procedure for Single Use Only

SQL2008: Lock a Stored Procedure for Single Use Only

Create a Custom Error Message, Designating an User assigned Error Number, starting at 50000, or higher, and a user designated Error Message.

USE Northwind GO   EXECUTE sp_addmessage     @msgnum   = 51001,     @severity = 16,     @msgtext  = N'Resource NOT Available',     @lang     = 'us_english',    @replace  = REPLACE

Create a Stored Procedure that Can be 'locked'

CREATE PROCEDURE dbo.Employees_U_LastName    (  @EmployeeID   int,       @LastName     varchar(20)    ) AS    BEGIN         SET TRANSACTION ISOLATION LEVEL REPEATABLE READ       BEGIN TRANSACTION         DECLARE @LockResult int         EXECUTE @LockResult = sp_getapplock           @Resource    = 'RepeatableRead_TRANSACTION',           @LockMode    = 'Exclusive',          @LockTimeout = 0              IF @LockResult <> 0             BEGIN                ROLLBACK TRANSACTION                RAISERROR ( 51001, 16, 1 )                RETURN             END            -- All code between the use of sp_getapplock above,          -- and sp_releaseapplock below will be restricted to           -- only one user at a time.              -- Ten Second delay for Demonstration Purposes          WAITFOR DELAY '00:00:10'          -- Remove these three lines for 'Normal' use            UPDATE Employees             SET LastName = @LastName             WHERE EmployeeID = @EmployeeID            EXECUTE sp_releaseapplock              @Resource = 'RepeatableRead_TRANSACTION'         COMMIT TRANSACTION      END  Demonstration

Open two separate Query Windows, and place the following code in one of the windows.
DO NOT Execute the code until both Query Windows are in place and connected to the database.

Query Window 1

   EXECUTE dbo.Employees_U_LastName       @EmployeeID = 1,       @LastName   = 'Davolio-Jones'         SELECT           EmployeeID,          LastName,          FirstName       FROM Employees       WHERE EmployeeID = 1 

Place the following code in Query window 2

Query Window 2

   EXECUTE dbo.Employees_U_LastName       @EmployeeID = 1,       @LastName   = 'Davolio'         SELECT           EmployeeID,          LastName,          FirstName       FROM Employees       WHERE EmployeeID = 1 

Execute the code in Query window 1, and then immediately execute the code in Query window 2.

Results in Query Window 2

Msg 51001, Level 16, State 1, Procedure Employees_U_LastName, Line 21 Resource NOT Available 

As you can see, it becomes possible to control code to single use only. 

Clean up the test environment

DROP PROCEDURE dbo.Employees_U_LastName 

Concurrency and Performance Considerations

Applications should capture the error, and handle appropriately, perhaps attempting to EXECUTE the query after a brief delay.

Finding the Last Occurrence of a Pattern in a String

When dealing with string data, one of the most useful Transact-SQL functions you can have in your toolbox is PATINDEX. Aside from it’s many creative uses (and there are quite a few), it allows you to search for an expression (including wildcard operators) within any valid SQL Server character type. It returns the position of the first occurrence of the pattern within the string, and returns zero (0) if the pattern is not found. As always, an example is worth 1000 bon mots:

SELECT PATINDEX('%c%', 'abcdefgabcdefga')

The above snippet returns 3, because the first instance of “c” within “abcdefgabcdefga” is at the third character.

On occasion, you may be required to find the last occurrence of the pattern rather than the first. This usually happens when you’re dealing with data from external systems, or when you’ve inherited custody of an inappropriately denormalized system (one where more than one “logical” data item has been stored in a single, concatenated field). I have the same requirement for my “mad science” series, so I developed a function to take care of it. Here it is:

CREATE FUNCTION dbo.REVERSEPATINDEX(@StringToFind    nvarchar(max),

                                  @StringToSearch nvarchar(max))

RETURNS bigint

AS

BEGIN

  --LastIndex will store the "previous" index of the pattern

  --while we search for the "next" index inside our string.

  DECLARE @LastIndex bigint, @NextIndex bigint


  --We will chop off the "searched" portion of our string

  --After each search iteration

  DECLARE @CurrentStringToSearch nvarchar(max)


  --Assign the value of the input parameter to @CurrentStringToSearch

  SET @CurrentStringToSearch = @StringToSearch


  --Grab the first occurrence, if it exists, using PATINDEX

  SET @NextIndex = PATINDEX(@StringToFind, @CurrentStringToSearch)

    
  --If we've found the pattern within the string, continue and find

  --subsequent occurrences until there are no more to find.

  WHILE @NextIndex > 0

  BEGIN

      --Add @NextIndex to @LastIndex, effectively storing within

      --@LastIndex the index of the occurence that we have just found,

      --based upon the original (non-truncated) string.

      SET @LastIndex = COALESCE(@LastIndex,0) + @NextIndex

    
      --Truncate @CurrentStringToSearch, removing the portion of the

      --string that we have already searched.

      SET @CurrentStringToSearch
          = RIGHT(@CurrentStringToSearch, LEN(@CurrentStringToSearch) - @NextIndex)

    
      --Find the NEXT occurence of the pattern in the remaining portion of

      --the string to search.

      SET @NextIndex = PATINDEX(@StringToFind, @CurrentStringToSearch)

  END


  --We will COALESCE @LastIndex and @NextIndex; @LastIndex will be NULL

  --if the pattern does not exist in the string (as the loop above will

  --never have been executed).

  RETURN  COALESCE(@LastIndex, @NextIndex)

END

GO

And to test:

SELECT dbo.REVERSEPATINDEX('%c%', 'abcdefgabcdefga')

Returns 10 – the correct answer, given that the last occurrence of “c” in “abcdefgabcdefga” is at the tenth character.