If a column is going to be used in more than one type of query, more than one column index type might be appropriate. Table 6-6 shows which index types make good combinations.
Add Index |
||||||
Existing Index |
HG |
HNG |
LF |
CMPa |
WD |
DATE, TIME, or DTTM |
HG |
- |
1 |
2 |
1 |
1 |
1 |
HNG |
1 |
- |
1 |
1 |
2 |
2 |
LF |
2 |
1 |
- |
1 |
2 |
1 |
1 = A reasonable combination 2 = An unlikely combination a. A CMP index applies to a pair of columns. Each of those columns always has at least one other index. |
||||||
The High_Group index in Sybase IQ Version
12 differs from earlier versions. For some columns you may want
both High_Group and High_Non_Group; previously,
it did not make sense to have both.A CMP index applies to a pair
of columns. Each of those columns always has at least one other
index.
