| Calculate the cost of a sort.
The cost of a sort includes the time spent in the sorter inserting
the rows into the sort, and the time spent in the sorter returning the
rows. Note that it does not include the cost of scanning the rows from
the source table, for insert into the sort.
Arguments to getSortCost(), should be the same as those to be passed to
TransactionController.createSort().
Parameters:
template - A row which is prototypical for the sort. Allrows inserted into the sort controller must have exactly the same number of columns as the template row. Every column in an inserted rowmust have the same type as the correspondingcolumn in the template.
Parameters:
columnOrdering - An array which specifies which columns participate in ordering - see interface ColumnOrdering for details. The columnreferenced in the 0th columnOrdering object iscompared first, then the 1st, etc.
Parameters:
alreadyInOrder - Indicates that the rows inserted into the sortcontroller will already be in order. This is usedto perform aggregation only.
Parameters:
estimatedInputRows - The number of rows that the caller estimateswill be inserted into the sort. This number mustbe >= 0.
Parameters:
estimatedExportRows - The number of rows that the caller estimateswill be exported by the sorter. For instance ifthe sort is doing duplicate elimination and allrows are expected to be duplicates then the estimatedExportRows would be 1. If no duplicateeliminate is to be done then estimatedExportRows would be the same as estimatedInputRows. This number must be >= 0.
Parameters:
estimatedRowSize - The estimated average row size of the rows being sorted. This is the client portion of the rowsize, it should not attempt to calculate Store's overhead. -1 indicates that the callerhas no idea (and the sorter will use 100 bytesin that case. Used by the sort to make good choices about in-memory vs. external sorting, and to size merge runs. The client is notexpected to estimate the per column/ per row overhead of raw store, just to make a guessabout the storage associated with each row (ie. reasonable estimates for some implementations would be 4 for int, 8 for long,102 for char(100), 202 for varchar(200), anumber out of hat for user types, ...). The cost of the sort.
exception:
StandardException - Standard exception policy. |