<div>
CAST(GETDATE() as date) will return the date part of GETDATE() without the time. 

<pre><code class="code-1 nolinks" id="code-20-42043124-1">SELECT DateCompleted
FROM dbo.tblSuperDateChecker
WHERE DateCompleted &gt;= CAST(GETDATE() as date)
</code></pre>
</div>

<div>
Perfect. Where do I put additional -30 days (today to 30 days ago)
</div>

<div>
here is another approach which allows the 30 days ago data to be presented on the same row as today
<pre><code class="code-10 nolinks" id="code-20-42044668-1">declare @today datetime
set @today = dateadd(dd, datediff(dd,0, getDate()), 0) -- this would be the normal line

SELECT top(1) t.DateCompleted, oa.P30DateCompleted
FROM tblSerialMasterPending t
OUTER APPLY(
 select top(1) DateCompleted P30DateCompleted
 from tblSerialMasterPending p30
 where p30.DateCompleted &gt;= dateadd(day,-30,@today) and p30.DateCompleted &lt; dateadd(day,-29,@today)
 order by p30.DateCompleted DESC
 ) oa
WHERE t.DateCompleted &gt;= @today and t.DateCompleted &lt; dateadd(day,30,@today)
ORDER BY t.DateCompleted DESC
</code></pre>
e.g.
<pre><code class="code-1 nolinks" id="code-20-42044668-2">+---------------------+---------------------+
| DateCompleted | P30DateCompleted |
+---------------------+---------------------+
| 10.03.2017 13:45:16 | 08.02.2017 13:14:15 |
+---------------------+---------------------+
</code></pre>
</div>

<div>
<div class="content wysiwyg-content">
I have this date format in my view (table) : &nbsp;2017-03-10 13:45:16.567 
 
I am trying to get today only in my view. I have tried the following: 
 
SELECT &nbsp; &nbsp; TOP (100) PERCENT DateCompleted 
FROM &nbsp; &nbsp; &nbsp; &nbsp; dbo.tblSuperDateChecker 
WHERE &nbsp; &nbsp; (DateCompleted = RTRIM(CONVERT(char(10), GETDATE(), 101))) 
 
SELECT &nbsp; &nbsp; TOP (100) PERCENT DateCompleted 
FROM &nbsp; &nbsp; &nbsp; &nbsp; dbo.tblSerialMasterPending 
WHERE &nbsp; &nbsp; (DateCompleted = CONVERT(Varchar(8), GETDATE(), 112)) 
 
I have piece of data that should be showing: (here is date filter removed). The top line should display because today is the 10th 
2017-03-10 13:45:16.567 
2017-03-09 13:45:13.550 
2017-03-09 13:45:10.540
</div>
</div>

I have this date format in my view (table) :  2017-03-10 13:45:16.567

I am trying to get today only in my view. I have tried the following:

SELECT     TOP (100) PERCENT DateCompleted
FROM         dbo.tblSuperDateChecker
WHERE     (DateCompleted = RTRIM(CONVERT(char(10), GETDATE(), 101)))

SELECT     TOP (100) PERCENT DateCompleted
FROM         dbo.tblSerialMasterPending
WHERE     (DateCompleted = CONVERT(Varchar(8), GETDATE(), 112))

I have piece of data that should be showing: (here is date filter removed). The top line should display because today is the 10th
2017-03-10 13:45:16.567
2017-03-09 13:45:13.550
2017-03-09 13:45:10.540

SQL 2008 - Date Filter for TODAY and TODAY-30 Days

Microsoft SQL Server 2008 is a suite of relational database management system (RDBMS) products providing multi-user database access functionality.Component services include integration (SSIS), reporting (SSRS), analysis (SSAS), data quality, master data, T-SQL and performance tuning. Major improvements include the  Always On technologies and support for unstructured data types.