The lookup condition defines when the lookup returns values from the lookup object. When you configure the lookup condition, you compare the value of one or more fields from the data flow with values in the lookup object.
A lookup condition includes an incoming field from the data flow, a field from the lookup object, and an operator. For flat file and database connections, you can use the following operators in a lookup condition:
•= (Equal to)
•< (Less than)
•> (Greater than)
•<= (Less than or equal to)
•>= (Greater than or equal to)
•!= (Not equal to)
For other connections and for Lookup transformations that use a dynamic cache, you can use the = (Equal to) operator in a lookup condition.
Note the following information about lookup conditions:
•When you enter multiple conditions, the mapping task evaluates the lookup conditions using the AND logical operator to join the conditions. It returns rows that match all of the lookup conditions.
•When you include multiple conditions, to optimize performance enter the conditions in the following order:
1= (Equal to)
2< (Less than), <= (Less than or equal to), > (Greater than), >= (Greater than or equal to)
3!= (Not equal to)
•The lookup condition matches null values. When an input field is NULL, the mapping task evaluates the NULL equal to null values in the lookup.
•In advanced mode, the mapping becomes invalid if the lookup condition contains a binary data type.
•If the lookup condition is completely parameterized, then you need to enter the lookup condition in the format:
<Lookup field><Operator><Incoming field>
If multiple conditions are required, join them with AND.