public interface RowOrdering
Modifier and Type | Field and Description |
---|---|
static int |
ASCENDING |
static int |
DESCENDING |
static int |
DONTCARE |
Modifier and Type | Method and Description |
---|---|
void |
addOrderedColumn(int direction,
int tableNumber,
int columnNumber)
Add a column to this RowOrdering in the current order position.
|
void |
addUnorderedOptimizable(Optimizable optimizable)
Add an unordered optimizable to this RowOrdering.
|
boolean |
alwaysOrdered(int tableNumber)
Ask whether the given table is always ordered.
|
void |
columnAlwaysOrdered(Optimizable optimizable,
int columnNumber)
Tell this RowOrdering that it is always ordered on the given column
of the given optimizable.
|
void |
copy(RowOrdering copyTo)
Copy the contents of this RowOrdering to the given RowOrdering.
|
boolean |
isColumnAlwaysOrdered(int tableNumber,
int columnNumber)
Return true if the column is always ordered.
|
void |
nextOrderPosition(int direction)
Move to the next order position for adding ordered columns.
|
void |
optimizableAlwaysOrdered(Optimizable optimizable)
Tell this RowOrdering that it is always ordered on the given optimizable
This is useful when considering a unique index where there is an
equality match on the entire key - in this case, all the columns
are ordered, regardless of the direction or position,
or even whether the columns are in the index.
|
boolean |
orderedOnColumn(int direction,
int tableNumber,
int columnNumber)
Tell whether this ordering is ordered on the given column.
|
boolean |
orderedOnColumn(int direction,
int orderPosition,
int tableNumber,
int columnNumber)
Tell whether this ordering is ordered on the given column in
the given position
|
void |
removeOptimizable(int tableNumber)
Tell this row ordering that it is no longer ordered on the given
table.
|
static final int ASCENDING
static final int DESCENDING
static final int DONTCARE
boolean orderedOnColumn(int direction, int orderPosition, int tableNumber, int columnNumber) throws StandardException
direction
- One of ASCENDING, DESCENDING, or DONTCARE
depending on the requirements of the caller.
An ORDER BY clause cares about direction,
while DISTINCT and GROUP BY do not.orderPosition
- The position in the ordering list. For example,
for ORDER BY A, B, position 0 has column A,
and position 1 has column B. Note that for an
ordering, more than one column can be in a single
ordering position: for example, in the query
SELECT * FROM S, T WHERE S.A = T.B ORDER BY T.B
columns S.A and T.B will be in the same ordering
positions because they are equal. Also, constant
values are considered ordered in all positions
(consider SELECT A FROM T WHERE A = 1 ORDER BY A).tableNumber
- The table number of the Optimizable containing
the column in questioncolumnNumber
- The column number in the table (one-based).StandardException
- Thrown on errorboolean orderedOnColumn(int direction, int tableNumber, int columnNumber) throws StandardException
direction
- One of ASCENDING, DESCENDING, or DONTCARE
depending on the requirements of the caller.
An ORDER BY clause cares about direction,
while DISTINCT and GROUP BY do not.tableNumber
- The table number of the Optimizable containing
the column in questioncolumnNumber
- The column number in the table (one-based).StandardException
- Thrown on errorvoid addOrderedColumn(int direction, int tableNumber, int columnNumber)
direction
- One of ASCENDING, DESCENDING, or DONTCARE.
DONTCARE can be used for things like columns
with constant value, and for one-row tables.tableNumber
- The table the column is in.columnNumber
- The column number in the table (one-based)void nextOrderPosition(int direction)
direction
- One of ASCENDING, DESCENDING, or DONTCARE.
DONTCARE can be used for things like columns
with constant value, and for one-row tables.void optimizableAlwaysOrdered(Optimizable optimizable)
optimizable
- The table in questionvoid columnAlwaysOrdered(Optimizable optimizable, int columnNumber)
optimizable
- The table in questioncolumnNumber
- The number of the column in question.boolean isColumnAlwaysOrdered(int tableNumber, int columnNumber)
tableNumber
- The table in questioncolumnNumber
- The number of the column in question.boolean alwaysOrdered(int tableNumber)
void removeOptimizable(int tableNumber)
tableNumber
- The number of the table to remove from
this RowOrdering.void addUnorderedOptimizable(Optimizable optimizable)
void copy(RowOrdering copyTo)
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