Modification of the sql loader control file

I am working on a script which uses Oracle SQL *Loader to load data into a table. However, anywhere I search about the control file of an sql loader I am seeing only statements like: "load data into table TABLE_NAME TRUNCATE FIELDS TERMINATED BY ';' TRAILING NULLCOLS ( Field1, Field2, Field3, Field4) ' Can I insert select statement in this control file ? I suppose want to verify if field3 in the incoming record has a certain value for which a record can be found in an existing table containing a similar field and if yes then it load the data and if no then it would send an output to a log file. For example, for the incoming record, say p, I want to verify if the count of records for (select * from table_k where field_demo = p.filed1) is greater than zero or not. If it is greater than zero then it would insert the record into the table otherwise show an output message to the log file.