My system is designed to handle large amounts of data. For example, it might have a relational table with a billion rows. The values for each column are stored

My system is designed to handle large amounts of data. For example, it might have a relational table with a billion rows. The values for each column are stored in such a way that separate threads can operate on different segments of the data. For example: if a query wants to find all addresses in an 'address' column that end in 'Avenue' and there are a billion unique addresses; then 10 separate threads might each look through 100 million values. The code has each thread gather its own set of results and only adds them to the final result set (shared) when the search completes. The shared object only needs to be locked once by each thread as it appends its results to the list. This avoids contention that might occur if each thread tried to add a single value to the shared list as it found it.