/*
* cume_dist
* return fraction betweeen 0 and 1 inclusive,
* which is described as NP / NR, where NP is the number of rows preceding or
* peers to the current row, and NR is the total number of rows, per spec.
*/
datum_t window_cume_dist(PG_FUNC_ARGS)
{
winobj_s* winobj = PG_WINOBJ();
rank_context *context;
bool up;
int64 totalrows = win_get_row_count(winobj);
ASSERT(totalrows > 0);
up = rank_up(winobj);
context = (rank_context *) win_get_partition(winobj, sizeof(rank_context));
if (up || context->rank == 1) {
/*
* The current row is not peer to prior row or is just the first, so
* count up the number of rows that are peer to the current.
*/
int64 row;
context->rank = win_get_current_position(winobj) + 1;
/*
* start from current + 1
*/
for (row = context->rank; row < totalrows; row++) {
if (!win_rows_are_peers(winobj, row - 1, row))
break;
context->rank++;
}
}
RET_FLOAT8((float8) context->rank / (float8) totalrows);
}
/*
* dense_rank
* Rank increases by 1 when key columns change.
*/
datum_t window_dense_rank(PG_FUNC_ARGS)
{
winobj_s* winobj = PG_WINOBJ();
rank_context *context;
bool up;
up = rank_up(winobj);
context = (rank_context*) win_get_partition(winobj, sizeof(rank_context));
if (up)
context->rank++;
RET_INT64(context->rank);
}
/*
* rank
* Rank changes when key columns change.
* The new rank number is the current row number.
*/
Datum
window_rank(PG_FUNCTION_ARGS)
{
WindowObject winobj = PG_WINDOW_OBJECT();
rank_context *context;
bool up;
up = rank_up(winobj);
context = (rank_context *)
WinGetPartitionLocalMemory(winobj, sizeof(rank_context));
if (up)
context->rank = WinGetCurrentPosition(winobj) + 1;
PG_RETURN_INT64(context->rank);
}
/*
* percent_rank
* return fraction between 0 and 1 inclusive,
* which is described as (RK - 1) / (NR - 1), where RK is the current row's
* rank and NR is the total number of rows, per spec.
*/
datum_t window_percent_rank(PG_FUNC_ARGS)
{
winobj_s* winobj = PG_WINOBJ();
rank_context *context;
bool up;
int64 totalrows = win_get_row_count(winobj);
ASSERT(totalrows > 0);
up = rank_up(winobj);
context = (rank_context*) win_get_partition(winobj, sizeof(rank_context));
if (up)
context->rank = win_get_current_position(winobj) + 1;
/* return zero if there's only one row, per spec */
if (totalrows <= 1)
RET_FLOAT8(0.0);
RET_FLOAT8((float8) (context->rank - 1) / (float8) (totalrows - 1));
}
/*
* percent_rank
* return fraction between 0 and 1 inclusive,
* which is described as (RK - 1) / (NR - 1), where RK is the current row's
* rank and NR is the total number of rows, per spec.
*/
Datum
window_percent_rank(PG_FUNCTION_ARGS)
{
WindowObject winobj = PG_WINDOW_OBJECT();
rank_context *context;
bool up;
int64 totalrows = WinGetPartitionRowCount(winobj);
Assert(totalrows > 0);
up = rank_up(winobj);
context = (rank_context *)
WinGetPartitionLocalMemory(winobj, sizeof(rank_context));
if (up)
context->rank = WinGetCurrentPosition(winobj) + 1;
/* return zero if there's only one row, per spec */
if (totalrows <= 1)
PG_RETURN_FLOAT8(0.0);
PG_RETURN_FLOAT8((float8) (context->rank - 1) / (float8) (totalrows - 1));
}
/*
* cume_dist
* return fraction betweeen 0 and 1 inclusive,
* which is described as NP / NR, where NP is the number of rows preceding or
* peers to the current row, and NR is the total number of rows, per spec.
*/
Datum
window_cume_dist(PG_FUNCTION_ARGS)
{
WindowObject winobj = PG_WINDOW_OBJECT();
rank_context *context;
bool up;
int64 totalrows = WinGetPartitionRowCount(winobj);
Assert(totalrows > 0);
up = rank_up(winobj);
context = (rank_context *)
WinGetPartitionLocalMemory(winobj, sizeof(rank_context));
if (up || context->rank == 1)
{
/*
* The current row is not peer to prior row or is just the first, so
* count up the number of rows that are peer to the current.
*/
int64 row;
context->rank = WinGetCurrentPosition(winobj) + 1;
/*
* start from current + 1
*/
for (row = context->rank; row < totalrows; row++)
{
if (!WinRowsArePeers(winobj, row - 1, row))
break;
context->rank++;
}
}
PG_RETURN_FLOAT8((float8) context->rank / (float8) totalrows);
}
