One of the nicer features in ColdFusion 11 was the addition of queryExecute. It lets you run a query from cfscript easier than using the component based system that was added in the past. However, a StackOverflow user discovered an interesting bug with it.
Scott J. posted a question to StackOverflow about something odd he saw in ColdFusion's debugging output when he used queryExecute. Imagine the following simple call:
data = queryExecute("select * from tblblogentries limit 0,1", {}, {datasource:"myblog"});
If you turn on ColdFusion Debugging, you would expect to see "data" as a query. Instead he saw this:
It looks like ColdFusion is assigning a temporary variable to the query before returning it to the variable you specify. If you run multiple queryExecute calls they use the same variable. If you use a tag-based query it works correctly. If you remember, the debug templates are simply ColdFusion files. I checked in there to ensure there wasn't a bug, but as far as I can see, it is working right.
Also, for fun, I did: _queryname_var0 = 9;
and yep - it gets overwritten. Oddly it won't exist in the Variables scope, but if you use it as a variable and then run queryExecute, it gets removed completely. I wouldn't go so far as to say queryExecute is unsafe to use, but, you may want to ensure you are not using a variable with the same name. It also makes debugging a bit more difficult as you will have multiple items in the report with the same name.
I've filed a bug report: https://bugbase.adobe.com/index.cfm?event=bug&id=3836702