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What constitutes a large table? While the size of a very large database (VLDB) is measured in hundreds of gigabytes, or even terabytes, the term does not necessarily indicate the size of individual tables within the database. A large database is one that does not perform as desired or one in which the operational or maintenance costs have gone beyond predefined maintenance or budgetary requirements. These requirements also apply to tables; a table can be considered large if the activities of other users or maintenance operations have a limiting affect on availability. For example, the sales table is considered large if performance is severely degraded or if the table is inaccessible during maintenance for two hours each day, each week, or even each month. In some cases, periodic downtime is acceptable, yet it can often be avoided or minimized by better design and partitioning implementations. While the term VLDB applies only to a database, for partitioning, it is more important to look at table size.