Multiple choice technology

Identify the False statement among the following :

  1. One can use Interval, Interval_top, Interval_bottom etc. modifiers in the key specifier of a Lookup file to search within a range.

  2. A common use of Lookup files is to process data records of multiple files if one of them is small enough to fit in memory, as a substitute of using Join component.

  3. Suppose we use a lookup expression as :- lookup("CUST_NAME_LKP", "Jack").cust_id -- Now if there are multiple records in the lookup file against the name "Jack", only the first matching cust_id value is returned.

  4. When we use a file as Lookup, the entire file is read into memory and accessed as a hash table.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Statement C is false. When a lookup file has multiple records matching the lookup key, the lookup function returns ALL matching records, not just the first one. To get only the first match, you would need to use additional functions or logic. The other statements are true: interval modifiers enable range searches, lookup files substitute for joins with small datasets, and lookup files are loaded into memory as hash tables.

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