public interface IndexDescriptor
Modifier and Type | Method and Description |
---|---|
int[] |
baseColumnPositions()
Returns an array of column positions in the base table.
|
int |
getKeyColumnPosition(int heapColumnPosition)
Returns the postion of a column.
|
java.lang.String |
indexType()
Returns the type of the index.
|
boolean[] |
isAscending()
Returns array of boolean telling asc/desc info for each index
key column for convenience of using together with baseColumnPositions
method.
|
boolean |
isAscending(java.lang.Integer keyColumnPosition)
Returns true if the specified column is ascending in the index
(1-based).
|
boolean |
isDescending(java.lang.Integer keyColumnPosition)
Returns true if the specified column is descending in the index
(1-based).
|
boolean |
isUnique()
Returns true if the index is unique.
|
boolean |
isUniqueWithDuplicateNulls()
Returns true if the index is duplicate keys only for null key parts.
|
int |
numberOfOrderedColumns()
Returns the number of ordered columns.
|
void |
setBaseColumnPositions(int[] baseColumnPositions)
set the baseColumnPositions field of the index descriptor.
|
void |
setIsAscending(boolean[] isAscending)
set the isAscending field of the index descriptor.
|
void |
setNumberOfOrderedColumns(int numberOfOrderedColumns)
set the numberOfOrderedColumns field of the index descriptor.
|
boolean isUnique()
boolean isUniqueWithDuplicateNulls()
int[] baseColumnPositions()
int getKeyColumnPosition(int heapColumnPosition)
Returns the position of a column within the key (1-based). 0 means that the column is not in the key. Same as the above method, but it uses int instead of Integer.
int numberOfOrderedColumns()
In the future, it will be possible to store non-ordered columns in an index. These will be useful for covered queries. The ordered columns will be at the beginning of the index row, and they will be followed by the non-ordered columns. For now, all columns in an index must be ordered.
java.lang.String indexType()
boolean[] isAscending()
boolean isAscending(java.lang.Integer keyColumnPosition)
boolean isDescending(java.lang.Integer keyColumnPosition)
void setBaseColumnPositions(int[] baseColumnPositions)
void setIsAscending(boolean[] isAscending)
void setNumberOfOrderedColumns(int numberOfOrderedColumns)
Apache Derby V10.10 Internals - Copyright © 2004,2014 The Apache Software Foundation. All Rights Reserved.