Adding in filters

    We left off with a very simple Select Statement that will pull all of the data without exception. But what about when you want to see specific data. At that point you want to add a filter, or in the case of SQL, you need to add a WHERE clause. The WHERE is the place in your statement you can specify exactly what you want SQL to show. There are many ways to filter your information, this is one of many we will cover. This is where you first start t get your feet wet with specifics.

    In the statement below we will add a very simple where condition. Once again, healthcare data is all about specifics, so lets start with a few of the details we like to see in healthcare analytics. (I plan on building a database with some examples of the type of data we want to see, but it takes time to make up phantom data)


SELECT  HEALTHPLAN

,[MEMBERIDTOUSE]
,[First Name]
,[Last Name]
,CONVERT (varchar (10),[enc_Date], 101) as [From Date]
,CONVERT (varchar (10),[enc_Date], 101) as [To Date]
,ProviderType1= ltrim(rtrim('20')),Diag1= CASE WHEN ltrim(rtrim(DX_Code)) Is NULL THEN ''
ELSE REPLACE (ltrim(rtrim(DX_Code)),'.','') END
,ProviderType2=''
,Diag2= ''
,ProviderType3=''
,Diag3= ''
,ProviderType4=''
,Diag4= ''
,ProviderType5=''
,Diag5= ''
,ProviderType6=''
,Diag6= ''
,ProviderType7=''
,Diag7= ''
,ProviderType8=''
,Diag8= ''
,ProviderType9=''
,Diag9= ''
FROM DATABASE_NAME.dbo.TABLE_NAMEwhere MEMBERIDTOUSE is not null and DX_Code is not null


 So in this statement we only want to those members that have data in the fields. This statement will exclude emmty field spaces for MEMBERIDTOUSE and DX_Code. There is alot in this script that we can cover, so we will continue to point back to it. Thats it for today, short and sweet. (That's what she said)


 FYI, we use [ ] when the field names are not connected, although I sometimes use them regardless of how the field is labeled.