Caching big data in application using MemoryCache

Possibly save 2 hours of your time: I have only encountered this more recently in an application that deals with big dataset.
In this scenario, the application needs to provide a feature to download full datasets. And this dataset is huge (~75MB to ~125MB) in size. And there are many datasets.
It took awhile to query this data and do some calculation and send it back to the client app. So we decide to cache this data at the application level using System.Runtime.Caching.MemoryCache for subsequent faster performance. As you can see, the problem can become bigger as more datasets are downloaded and cached.
There are few options in no particular order:
  1. More expensive but easiest solution may be to increase memory on physical server to account for the size of the cache that can grow to.
  2. Recycle the application pool after reaching maximum virtual memory usage. See here for specifics.
  3. Set the CacheMemoryLimit on the MemoryCache object. This sets the amount of memory on the computer, in bytes, that can be used by the cache.

 

 

 

SSIS – Foreach Loop Container and Execute SQL Task

Possibly save 2 hours of your time: When you work on SSIS to do ETL, you may often encounter the need to loop through some records and process each record one at a time.
You can use the following steps:
  • Execute SQL Task – Get the records that need to be processed
  • Foreach Loop Container – Loop through each record
    • Execute SQL Task – Process one record at a time
ssis_foreachloop_1

Create two user variables:

  • i.e. CollectionIDs (Object) – One for collection of the IDs to be processed
  • i.e. CollectionID (Int32) – the current ID to be processed

 

The following will get the Full result set based on a select query. In this case as you can see on the SQLStatement, we select a primary key ID column from a table based on some criteria input. i.e. select ID from someTable i inner join anotherTable d on i.SourceID = d.SourceID where d.Title = ?

ssis_foreachloop_2

You may use a parameter input via Parameter Mapping in your query (i.e. select id from table where name = ‘someVariable’).

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Now you want to store your Result Set into a user variable for looping through later.

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In the Foreach Loop Editor, you can use Foreach ADO Enumerator, and select the collection user variable.

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We want to a user variable to store the current processed id.

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You can specify a query or stored procedure to process each record.

i.e. [schema].[usp_ProcessRecord] NULL, ?

The above example has two input variables where one is always NULL and the ? represents an input parameter.

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In this example, the input is a large integer.

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Regular Expressions (Regex)

Possibly save 1 hour of your time: There are many times where I have to do some sort of pattern matching and then extract certain parameters.

Regex can be helpful in matching some sort of field requirement or even better, it can help extract parameters from the matching pattern.

The Regex object has a Groups property in which if something matches, then the first array element returns the entire matching pattern. And within the pattern you may define multiple groups of patterns and so the second array element will return the first group pattern and third array element will return the second group pattern.

The following are two examples of usage.


[Test]
 public void TestRegex()
 {
 var text = "123-4567890";

//brackets are groups
 var regex = new Regex(@"(\d\d\d)-(\d\d\d\d\d\d\d)");
 var match = regex.Match(text);

Assert.That(match.Success, Is.True);
 Assert.That(match.Groups[0].Value, Is.EqualTo(text));
 Assert.That(match.Groups[1].Value, Is.EqualTo("123"));
 Assert.That(match.Groups[2].Value, Is.EqualTo("4567890"));
 }

[Test]
 public void TestRegex2()
 {
 var text = "DatasetName='Population',ParameterID=12)";

//* match zero or more times
 //+ match once or more

//brackets are groups
 var regex = new Regex(@",ParameterID=(\d+)");
 var match = regex.Match(text);

Assert.That(match.Success, Is.True);
 Assert.That(match.Groups[0].Value, Is.EqualTo(",ParameterID=12"));
 Assert.That(match.Groups[1].Value, Is.EqualTo("12"));

 }

Entity Framework transaction handling via SaveChanges

Possibly save 1 hour of your time: A common question that was asked is how to handle transaction within your application.
Fortunately, if you are using Entity Framework, it already does the heavy lifting work for you.
When you modify your entities in the application, it will track model and property changes behind the scene. And then when you call the following line of code, it will persists all updates to the database and resets change tracking in the object context.
objectContext.SaveChanges();

 

ObjectContext is the object that represents the database connection and its entities.

There may be situations when you may call this more than once in a request to create multiple transactions. I cannot think of a reason right now, but just remember that this acts like a commit transaction as each SaveChanges call will create a new transaction.

However, there are also cases where you may have more than one context to deal with. In that case you may pull data from one database and save them to another database. In this case, you may want to put both contexts’ SaveChanges calls in a TransactionScope to protect this as one atomic transaction.

References:

ObjectContext.SaveChanges Method ()

https://msdn.microsoft.com/en-us/library/bb336792(v=vs.110).aspx

Blogging source code on WordPress

Possibly save 4 hours of your time: If you are programmer who has started a blog, you may want to display your source code.  Then you may try to find plugins to help support better display of your code. However I find most plugins are hard to use and not intuitive.

WordPress does have original support for displaying code with colors based on language type.

public void DisplayWordpressCodeWithColor()
{
}

For supported language, please see list in the following link:

https://en.support.wordpress.com/code/posting-source-code/

Setup SQL Server Integration Services environment and SQL Agent Job to run deployed SSIS package

Possibly save 8 hours of your time: After you create SSIS package and build the project (bin folder should have .ispac file), the next step is to deploy that to a Microsoft SQL Server instance environment and have a scheduled job to run the package. It is not trivial to setup a proper environment. The steps below are targeting Microsoft SQL Server 2012.

Pre-requisites

  • Please make sure that you have SSISDB catalog under Integration Services Catalogs already created. If not, you can right click and choose Create Catalog.

ssisdb

  • A specific user or system user permission will be needed to run the job to execute the package. From here on we call this user the system user.
  • If the package requires read and/or write access to specific database, provide the following database role permissions as needed to the system user:
    • db_datareader
    • db_datawriter
    • SSIS
  • If the package requires execute permission for specific schema on a specific database, provide the following permissions as needed to the system user:
    • Execute
    • Alter (if using bulk insert tasks in SSIS)
  • For msdb system database, the system user needs to be added to Security > Users. Under Owned Schemas, check SQLAgentUserRole.
  • For SSISDB database, the system user needs to be added to Security > Users.
  • The database administrator who will be running the command script to create the job to run the package will need sysadmin role.
  • If you want to receive SSIS job notification on success or failure, you will need to setup an account under Management > Database Mail. Then right click SQL Server Agent, click Alert System and Enable mail profile and choose the account profile created.

Script Implementation

  • Please see at the bottom for the script. The scripts can be run in command prompt directly or embed in a .cmd script file first. Any word surround by %% are variables that you can set.
  • cmd Script will create
    • folder in SSISDB
    • Deploy packages via .ispac
    • run the following SQL script
  • SQL Script will create
    • delete previous existing job
    • create Credential
    • create Proxy
    • create Alerts
    • create SQL Agent Job via .sql
    • add package(s) to the job
    • add job schedule

Post-requisites

  • Setup environment variables if your packages requires specific configuration for this environment – Integration Services Catalog >> SSISDB >> Project >> Environments
  • Update Project Variable Environment
    • Right click project. Select Configure.
    • Under References, add the environment created previously.
    • Under Parameters, edit the same values as in the environment section to use environment variables.
  • Set project level permissions
    • At the SSISDB folder level, add system identity user account with read, execute objects and read objects permissions
    • At the projects level, add read and execute permission for the system identity user.
  • Setup working folder permissions for system user if using working folder (typically if data files are involved in the package, they need to be somewhere)

Script – create folder in SSISDB

set sqlcmdpath=”C:\Program Files\Microsoft SQL Server\110\Tools\Binn\sqlcmd.exe”

REM Create folder in SSISDB

echo Creating folder in SSISDB if not exists…
echo %sqlcmdpath% -S %serverName% -d ssisdb -Q “if not exists(select 1 from internal.folders where name = ‘%folder%’) exec catalog.create_folder %folder%”
%sqlcmdpath% -S %serverName% -d ssisdb -Q “if not exists(select 1 from internal.folders where name = ‘%folder%’) exec catalog.create_folder %folder%”

echo *******************************************************

Script – deploy packages via .ispac file

set isdeploymentwizard=”C:\Program Files\Microsoft SQL Server\110\DTS\Binn\isdeploymentwizard.exe”

REM Deploy the ETL
echo ETL Deployment is running…
echo %isdeploymentwizard% /S /ST:File /SP:”yourProjectName.ispac” /DS:%serverName% /DP:/SSISDB/%folder%/%project%
%isdeploymentwizard% /S /ST:File /SP:”yourProjectName.ispac” /DS:%serverName% /DP:/SSISDB/%folder%/%project%
echo ETL Deployment Completed
echo *******************************************************

Note: If you get error 0xC0011008 such as “the package failed to load due to error error loading from xml”, ensure you are targeting the right version of database via project properties.

Script – to run the following SQL script in one file with passed in parameters

set sqlcmdpath=”C:\Program Files\Microsoft SQL Server\110\Tools\Binn\sqlcmd.exe”

REM Create SQL Agent Job
echo Creating SQL Agent Job…
echo %sqlcmdpath% -S %serverName% -i %jobSQL% -v identity=”%id%” password=”%pass%” operator=”%oper%” environmentId=”%envId%”
%sqlcmdpath% -S %serverName% -i %jobSQL% -v identity=”%id%” password=”%pass%” operator=”%oper%” environmentId=”%envId%”
echo SQL Agent Job has been created

Delete previous existing job

USE [msdb]

GO
–Clean up SQL Agent Job

DECLARE @jobId BINARY(16)

SELECT @jobId = job_id FROM msdb.dbo.sysjobs WHERE (name = N’Your Job Name’)

IF (@jobId IS NOT NULL)    EXEC msdb.dbo.sp_delete_job @jobId go

Create Credential

–Create Credential Note: change the credential name

use master

go

IF EXISTS (SELECT 1 FROM sys.credentials WHERE name = N’Your Credential Name’) DROP credential [Your Credential Name]

go

create credential [Your Credential Name] with identity = N’$(identity)’, secret = N’$(password)’go

Create Proxy

–Create Proxy Note: change the proxy name

USE msdb

GO

IF EXISTS (SELECT 1 FROM msdb.dbo.sysproxies WHERE name = N’Your Proxy Name’) EXEC dbo.sp_delete_proxy @proxy_name = N’Your Proxy Name’

GO

EXEC msdb.dbo.sp_add_proxy @proxy_name=N’Your Proxy Name’,@credential_name=N’Your Credential Name’, @enabled=1

GO

EXEC msdb.dbo.sp_grant_proxy_to_subsystem @proxy_name=N’Your Proxy Name’, @subsystem_id=11GOEXEC msdb.dbo.sp_grant_login_to_proxy @proxy_name=N’Your Proxy Name’, @login_name=N’$(identity)’

GO

Create Alerts

–Create Operator

USE [msdb]

GO

IF EXISTS(SELECT 1 FROM msdb.dbo.sysoperators WHERE name = N’Your Operator Name’) EXEC sp_delete_operator @name=N’Your Operator Name’

GO

EXEC msdb.dbo.sp_add_operator @name=N’Your Operator Name’,  @enabled=1,  @weekday_pager_start_time=90000,  @weekday_pager_end_time=180000,  @saturday_pager_start_time=90000,  @saturday_pager_end_time=180000,  @sunday_pager_start_time=90000,  @sunday_pager_end_time=180000,  @pager_days=0,  @email_address=N’$(operator)’,  @category_name=N'[Uncategorized]’

GO

Create SQL Agent Job

 

–Create SQLAgent Job

USE [msdb]

GO
BEGIN TRANSACTION

DECLARE @ReturnCode INT

SELECT @ReturnCode = 0

IF NOT EXISTS (SELECT name FROM msdb.dbo.syscategories WHERE name=N'[Uncategorized (Local)]’ AND category_class=1)

BEGIN

EXEC @ReturnCode = msdb.dbo.sp_add_category @class=N’JOB’, @type=N’LOCAL’, @name=N'[Uncategorized (Local)]’IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback
END
DECLARE @jobId BINARY(16)

EXEC @ReturnCode =  msdb.dbo.sp_add_job @job_name=N’Your Job Name’,  @enabled=1,  @notify_level_eventlog=0,  @notify_level_email=2,  @notify_level_netsend=0,  @notify_level_page=0,  @delete_level=0,  @description=N’No description available.’,  @category_name=N'[Uncategorized (Local)]’,  @owner_login_name=N’$(identity)’,  @notify_email_operator_name=N’Your Job Name’, @job_id = @jobId OUTPUTIF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback

Add package to the job

EXEC @ReturnCode = msdb.dbo.sp_add_jobstep @job_id=@jobId, @step_name=N’Your Step Name’,
@step_id=1,
@cmdexec_success_code=0,
@on_success_action=3,
@on_success_step_id=0,
@on_fail_action=2,
@on_fail_step_id=0,
@retry_attempts=0,
@retry_interval=0,
@os_run_priority=0, @subsystem=N’SSIS’,
@command=N’/ISSERVER “\”\SSISDB\Your Folder Name\Your Project Name\Your Package Name.dtsx\”” /SERVER “\”$(serverName)\”” /ENVREFERENCE $(environmentId) /Par “\”$ServerOption::LOGGING_LEVEL(Int16)\””;1 /Par “\”$ServerOption::SYNCHRONIZED(Boolean)\””;True /CALLERINFO SQLAGENT /REPORTING E’,
@database_name=N’master’,
@flags=0,
@proxy_name=N’Your Proxy Name’
IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback

EXEC @ReturnCode = msdb.dbo.sp_update_job @job_id = @jobId, @start_step_id = 1

IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback

Note: You can repeat this to add more packages as steps in your job.

Add Job Schedule
EXEC @ReturnCode = msdb.dbo.sp_add_jobschedule @job_id=@jobId, @name=N’Your Schedule Name’,  @enabled=1,  @freq_type=4,  @freq_interval=1,  @freq_subday_type=8,  @freq_subday_interval=12,  @freq_relative_interval=0,  @freq_recurrence_factor=0,  @active_start_date=20160616,  @active_end_date=99991231,  @active_start_time=0,  @active_end_time=235959,  @schedule_uid=N’d5de52a3-a8e8-49ca-92d0-fbbc3ee10098′

IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback

EXEC @ReturnCode = msdb.dbo.sp_add_jobserver @job_id = @jobId, @server_name = N’$(serverName)’

IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback

COMMIT TRANSACTION

GOTO EndSave

QuitWithRollback:

IF (@@TRANCOUNT > 0) ROLLBACK TRANSACTION

EndSave:
GO

 

 

Download SQL Server Data Tools (SSDT) 17.1 for Visual Studio 2015 (SQL Server Integration Services – SSIS – project template)

Possibly save 1 hour of your time: This is a quick reference guide for getting the SSIS project template within Visual Studio 2015.

Download link here https://go.microsoft.com/fwlink/?linkid=849393

Source: https://docs.microsoft.com/en-us/sql/ssdt/download-sql-server-data-tools-ssdt

Once you download you can just double click to run the installation. You can check the following features that you need. I need SSIS so I will check SQL Server Integration Services.

install SSDT vs2015

Then you will have to agree to license terms.

If you select all features, it will take about 1 hour to install.

Once install is completed, open Visual Studio 2015, and go to File > New Project, you should be able to select the following Business Intelligence > Integration Services > Integration Services Project template.

ssis template vs2015

 

 

OData syntax

Possibly save 1 hour of your time: This is a quick reference guide for querying OData service. You can query as follows with the code shown below respectively.

Top 5 records

Filter based on some elementName with value ‘some Text’. Notice it uses eq as equal and %27 as single quote and space as +.

  • $top=5
  • $filter=elementName+eq+%27some+Text%27

 

User Interface testing

Possibly save many hours of your time: As a developer you may end up spending a lot of time testing your web application from the user interface.

There is a Firefox browser plugin tool named Selenium IDE that you can follow the instructions below to download. Once you download, you can create test suite and within test suite you can add test case. For each test case, you can click on the red circle (Record button) to record your actions. So you will have two Firefox browser windows, one where you will browse to your website and start performing actions and the other window (Selenium IDE) will record your actions and you can playback later to repeat the UI test. This will save you a lot of time in the future for repetitive tasks of testing. You can use all kinds of verify commands to test your labels, values on your display.

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se_2

se_3

se_4

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It will then ask you to restart Firefox.

se_6

Once restart, you can open the tool by going to menu icon and click on Developer, then choose Selenium IDE.

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Then it will open the Selenium IDE window.

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Some function tips:

If some elements take time to load, use waitForText rather than verifyText. You can also use pause function.

You can use store command to store variable.

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Then you can use it in other functions with $ and curly brackets notation.