Chapter 6. DB2 Indexing and Hashing Guidelines

You can create indexes on DB2 table columns to speed up query processing. An index uses pointers to actual data to more efficiently access specific pieces of data. Once created, DB2 automatically maintains each index as data is added, modified, and deleted from the table. As data is selected from the table, DB2 can choose to use the index to access the data more efficiently. It is important to remember that index modification and usage is automatic—you do not need to tell DB2 to modify indexes as data changes nor can you tell DB2 to use a particular index to access data. This ...

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