Script component runtime error

Question

I have a  package to update and create contacts from a database to an application. So far it is working fine. But if one of the input columns has null value it throws this error:
Condition for attribute 'new_lapinterpreter.new_interpreterlanguage': null is not a valid value for an attribute. Use 'Null' or 'NotNull' conditions instead.
I've used lookup transformation to avoid duplicate insertions and mapped the columns accordingly.
Here is my code:
public override void ContactInput_ProcessInputRow(ContactInputBuffer Row)
bool hasDulicate = false;
FilterExpression codeFilter = new FilterExpression(LogicalOperator.And);
codeFilter.AddCondition("new_interpretername", ConditionOperator.Equal, Row.fullname);
codeFilter.AddCondition("new_interpreterlanguage", ConditionOperator.Equal, Row.newprimarylanguage);
codeFilter.AddCondition("new_emailintlap", ConditionOperator.Equal, Row.emailaddress1);
codeFilter.AddCondition("new_primaryphoneintlap", ConditionOperator.Equal, Row.mobilephone);
QueryExpression query = new QueryExpression
EntityName = "new_lapinterpreter",
ColumnSet = new ColumnSet(true),
Criteria = codeFilter
EntityCollection records = _orgService.RetrieveMultiple(query);
int totalrecords = records.Entities.Count;
foreach (Entity record in records.Entities)
if (record["new_interpretername"] != null)
record["new_interpretername"] = Row.fullname;
if (record["new_interpreterlanguage"] != null)
record["new_interpreterlanguage"] = Row.newprimarylanguage;
if (record["new_emailintlap"] != null)
record["new_emailintlap"] = Row.emailaddress1;
if (record["new_primaryphoneintlap"] != null)
record["new_primaryphoneintlap"] = Row.mobilephone;
_orgService.Update(record);
hasDulicate = true;
if (hasDulicate == false)
var contact = new Entity("new_lapinterpreter");
if (!Row.fullname_IsNull)
contact["new_interpretername"] = Row.fullname;
if (!Row.newprimarylanguage_IsNull)
contact["new_interpreterlanguage"] = Row.newprimarylanguage;
if (!Row.emailaddress1_IsNull)
contact["new_emailintlap"] = Row.emailaddress1;
if (!Row.mobilephone_IsNull)
contact["new_primaryphoneintlap"] = Row.mobilephone;
_orgService.Create(contact);
Thanks

Answer 1

Thanks guys.
But the exception is thrown on this line.
EntityCollection records = _orgService.RetrieveMultiple(query);
If one of the columns value(Row.ColumnValue) in Filterexpression is null, the query is returning 0 columnset and throwing this exception.
Condition for attribute 'new_lapinterpreter.(whateverColumn is null)': null is not a valid value for an attribute. Use 'Null' or 'NotNull' conditions instead.
How do I check for Row null value in the filterexpression?
Thanks