query a list

The code below creates a list like this:  smith,jones,walsh,fox <cfloop list="#form.LastName#" index="i"> <cfquery name="getNames" datasource="MyDB"> select LastName from Employee where LastName= '#i#' </cfquery> </cfloop>

No, it doesn't. You need extra code to create such a list from the queries.

Two things seem to contradict each other here. The field form.LastName seems to represent just one last name, yet the loop  suggests a  list of last names.

Even if form.LastName represents a list, the construction of loop and query is inefficient. It is a waste of CPU resources to run a query at every step of the loop.

Is it possible to then query the employee table to find all records whose lastname does not equal smith or jones or walsh or fox?  If so, what is the best way to do that?

Suppose the starting point is a list like "smith,jones,walsh,fox". Then you could proceed as follows

<cfset lastNameList = "smith,jones,walsh,fox">

<!--- put single quotes around each name --->
<cfset qualifiedNameList = listQualify(lastNameList,"'",",","CHAR")>

<cfquery name="getNames" datasource="myDB">
select lastName from Employee where lastName NOT IN (#preservesinglequotes(qualifiedNameList)#)
</cfquery>

The SQL IN operator, or in your case the NOT IN operator.

SELECT LastName
FROM Employee
WHERE LastName NOT IN <cfqueryparam value="#listOfNames#" list='yes' cfsqltype="cf_sql_varchar">

P.S.  Yes you could do that without the <cfqueryparam...> tag, but why would anybody do that any more.