See the following table for advantages and disadvantages of using a DATE, TIME, or DTTM index.
Advantages |
Disadvantages |
|---|---|
Queries with date, time, or datetime quantities are resolved more quickly than with other index types. You can create and drop a DATE, TIME, or DTTM index. |
Uses more disk space than HNG index. Fast equality still requires LF or HG index. You can use these indexes only if data in the column is DATE, TIME, DATETIME, or TIMESTAMP data type. |
The following restrictions currently apply to DATE, TIME, and DTTM indexes:
Cannot use the UNIQUE keyword.
Can only be created on a single column.
Do not support date parts Calyearofweek, Calweekofyear, Caldayofweek, Dayofyear, Millisecond.
