Q&A
| Q1: | Does an index actually take up space the way a table does? |
| A1: | Yes. An index takes up physical space in a database. In fact, an index can become much larger than the table for which the index was created. |
| Q2: | If you drop an index for a batch job to complete faster, how long does it take to re-create the index? |
| A2: | Many factors are involved, such as the size of the index being dropped, CPU usage, and the machine's power. |
| Q3: | Should all indexes be unique indexes? |
| A3: | No. Unique indexes allow no duplicate values. There may be a need for the allowance of duplicate values in a table. |
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