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-rw-r--r--src/backend/access/tablesample/bernoulli.c69
-rw-r--r--src/backend/access/tablesample/system.c48
-rw-r--r--src/backend/access/tablesample/tablesample.c94
3 files changed, 106 insertions, 105 deletions
diff --git a/src/backend/access/tablesample/bernoulli.c b/src/backend/access/tablesample/bernoulli.c
index c91f3f593e5..563a9168f0f 100644
--- a/src/backend/access/tablesample/bernoulli.c
+++ b/src/backend/access/tablesample/bernoulli.c
@@ -27,13 +27,15 @@
/* tsdesc */
typedef struct
{
- uint32 seed; /* random seed */
- BlockNumber startblock; /* starting block, we use ths for syncscan support */
+ uint32 seed; /* random seed */
+ BlockNumber startblock; /* starting block, we use ths for syncscan
+ * support */
BlockNumber nblocks; /* number of blocks */
BlockNumber blockno; /* current block */
- float4 probability; /* probabilty that tuple will be returned (0.0-1.0) */
+ float4 probability; /* probabilty that tuple will be returned
+ * (0.0-1.0) */
OffsetNumber lt; /* last tuple returned from current block */
- SamplerRandomState randstate; /* random generator tsdesc */
+ SamplerRandomState randstate; /* random generator tsdesc */
} BernoulliSamplerData;
/*
@@ -42,10 +44,10 @@ typedef struct
Datum
tsm_bernoulli_init(PG_FUNCTION_ARGS)
{
- TableSampleDesc *tsdesc = (TableSampleDesc *) PG_GETARG_POINTER(0);
- uint32 seed = PG_GETARG_UINT32(1);
- float4 percent = PG_ARGISNULL(2) ? -1 : PG_GETARG_FLOAT4(2);
- HeapScanDesc scan = tsdesc->heapScan;
+ TableSampleDesc *tsdesc = (TableSampleDesc *) PG_GETARG_POINTER(0);
+ uint32 seed = PG_GETARG_UINT32(1);
+ float4 percent = PG_ARGISNULL(2) ? -1 : PG_GETARG_FLOAT4(2);
+ HeapScanDesc scan = tsdesc->heapScan;
BernoulliSamplerData *sampler;
if (percent < 0 || percent > 100)
@@ -77,14 +79,13 @@ tsm_bernoulli_init(PG_FUNCTION_ARGS)
Datum
tsm_bernoulli_nextblock(PG_FUNCTION_ARGS)
{
- TableSampleDesc *tsdesc = (TableSampleDesc *) PG_GETARG_POINTER(0);
- BernoulliSamplerData *sampler =
- (BernoulliSamplerData *) tsdesc->tsmdata;
+ TableSampleDesc *tsdesc = (TableSampleDesc *) PG_GETARG_POINTER(0);
+ BernoulliSamplerData *sampler =
+ (BernoulliSamplerData *) tsdesc->tsmdata;
/*
- * Bernoulli sampling scans all blocks on the table and supports
- * syncscan so loop from startblock to startblock instead of
- * from 0 to nblocks.
+ * Bernoulli sampling scans all blocks on the table and supports syncscan
+ * so loop from startblock to startblock instead of from 0 to nblocks.
*/
if (sampler->blockno == InvalidBlockNumber)
sampler->blockno = sampler->startblock;
@@ -116,7 +117,7 @@ tsm_bernoulli_nextblock(PG_FUNCTION_ARGS)
* tuples have same probability of being returned the visible and invisible
* tuples will be returned in same ratio as they have in the actual table.
* This means that there is no skew towards either visible or invisible tuples
- * and the number returned visible tuples to from the executor node is the
+ * and the number returned visible tuples to from the executor node is the
* fraction of visible tuples which was specified in input.
*
* This is faster than doing the coinflip in the examinetuple because we don't
@@ -128,12 +129,12 @@ tsm_bernoulli_nextblock(PG_FUNCTION_ARGS)
Datum
tsm_bernoulli_nexttuple(PG_FUNCTION_ARGS)
{
- TableSampleDesc *tsdesc = (TableSampleDesc *) PG_GETARG_POINTER(0);
- OffsetNumber maxoffset = PG_GETARG_UINT16(2);
- BernoulliSamplerData *sampler =
- (BernoulliSamplerData *) tsdesc->tsmdata;
- OffsetNumber tupoffset = sampler->lt;
- float4 probability = sampler->probability;
+ TableSampleDesc *tsdesc = (TableSampleDesc *) PG_GETARG_POINTER(0);
+ OffsetNumber maxoffset = PG_GETARG_UINT16(2);
+ BernoulliSamplerData *sampler =
+ (BernoulliSamplerData *) tsdesc->tsmdata;
+ OffsetNumber tupoffset = sampler->lt;
+ float4 probability = sampler->probability;
if (tupoffset == InvalidOffsetNumber)
tupoffset = FirstOffsetNumber;
@@ -142,8 +143,8 @@ tsm_bernoulli_nexttuple(PG_FUNCTION_ARGS)
/*
* Loop over tuple offsets until the random generator returns value that
- * is within the probability of returning the tuple or until we reach
- * end of the block.
+ * is within the probability of returning the tuple or until we reach end
+ * of the block.
*
* (This is our implementation of bernoulli trial)
*/
@@ -183,9 +184,9 @@ tsm_bernoulli_end(PG_FUNCTION_ARGS)
Datum
tsm_bernoulli_reset(PG_FUNCTION_ARGS)
{
- TableSampleDesc *tsdesc = (TableSampleDesc *) PG_GETARG_POINTER(0);
- BernoulliSamplerData *sampler =
- (BernoulliSamplerData *) tsdesc->tsmdata;
+ TableSampleDesc *tsdesc = (TableSampleDesc *) PG_GETARG_POINTER(0);
+ BernoulliSamplerData *sampler =
+ (BernoulliSamplerData *) tsdesc->tsmdata;
sampler->blockno = InvalidBlockNumber;
sampler->lt = InvalidOffsetNumber;
@@ -200,14 +201,14 @@ tsm_bernoulli_reset(PG_FUNCTION_ARGS)
Datum
tsm_bernoulli_cost(PG_FUNCTION_ARGS)
{
- PlannerInfo *root = (PlannerInfo *) PG_GETARG_POINTER(0);
- Path *path = (Path *) PG_GETARG_POINTER(1);
- RelOptInfo *baserel = (RelOptInfo *) PG_GETARG_POINTER(2);
- List *args = (List *) PG_GETARG_POINTER(3);
- BlockNumber *pages = (BlockNumber *) PG_GETARG_POINTER(4);
- double *tuples = (double *) PG_GETARG_POINTER(5);
- Node *pctnode;
- float4 samplesize;
+ PlannerInfo *root = (PlannerInfo *) PG_GETARG_POINTER(0);
+ Path *path = (Path *) PG_GETARG_POINTER(1);
+ RelOptInfo *baserel = (RelOptInfo *) PG_GETARG_POINTER(2);
+ List *args = (List *) PG_GETARG_POINTER(3);
+ BlockNumber *pages = (BlockNumber *) PG_GETARG_POINTER(4);
+ double *tuples = (double *) PG_GETARG_POINTER(5);
+ Node *pctnode;
+ float4 samplesize;
*pages = baserel->pages;
diff --git a/src/backend/access/tablesample/system.c b/src/backend/access/tablesample/system.c
index 1412e511faf..1d834369a4b 100644
--- a/src/backend/access/tablesample/system.c
+++ b/src/backend/access/tablesample/system.c
@@ -31,9 +31,9 @@
typedef struct
{
BlockSamplerData bs;
- uint32 seed; /* random seed */
+ uint32 seed; /* random seed */
BlockNumber nblocks; /* number of block in relation */
- int samplesize; /* number of blocks to return */
+ int samplesize; /* number of blocks to return */
OffsetNumber lt; /* last tuple returned from current block */
} SystemSamplerData;
@@ -44,11 +44,11 @@ typedef struct
Datum
tsm_system_init(PG_FUNCTION_ARGS)
{
- TableSampleDesc *tsdesc = (TableSampleDesc *) PG_GETARG_POINTER(0);
- uint32 seed = PG_GETARG_UINT32(1);
- float4 percent = PG_ARGISNULL(2) ? -1 : PG_GETARG_FLOAT4(2);
- HeapScanDesc scan = tsdesc->heapScan;
- SystemSamplerData *sampler;
+ TableSampleDesc *tsdesc = (TableSampleDesc *) PG_GETARG_POINTER(0);
+ uint32 seed = PG_GETARG_UINT32(1);
+ float4 percent = PG_ARGISNULL(2) ? -1 : PG_GETARG_FLOAT4(2);
+ HeapScanDesc scan = tsdesc->heapScan;
+ SystemSamplerData *sampler;
if (percent < 0 || percent > 100)
ereport(ERROR,
@@ -80,9 +80,9 @@ tsm_system_init(PG_FUNCTION_ARGS)
Datum
tsm_system_nextblock(PG_FUNCTION_ARGS)
{
- TableSampleDesc *tsdesc = (TableSampleDesc *) PG_GETARG_POINTER(0);
- SystemSamplerData *sampler = (SystemSamplerData *) tsdesc->tsmdata;
- BlockNumber blockno;
+ TableSampleDesc *tsdesc = (TableSampleDesc *) PG_GETARG_POINTER(0);
+ SystemSamplerData *sampler = (SystemSamplerData *) tsdesc->tsmdata;
+ BlockNumber blockno;
if (!BlockSampler_HasMore(&sampler->bs))
PG_RETURN_UINT32(InvalidBlockNumber);
@@ -99,10 +99,10 @@ tsm_system_nextblock(PG_FUNCTION_ARGS)
Datum
tsm_system_nexttuple(PG_FUNCTION_ARGS)
{
- TableSampleDesc *tsdesc = (TableSampleDesc *) PG_GETARG_POINTER(0);
- OffsetNumber maxoffset = PG_GETARG_UINT16(2);
- SystemSamplerData *sampler = (SystemSamplerData *) tsdesc->tsmdata;
- OffsetNumber tupoffset = sampler->lt;
+ TableSampleDesc *tsdesc = (TableSampleDesc *) PG_GETARG_POINTER(0);
+ OffsetNumber maxoffset = PG_GETARG_UINT16(2);
+ SystemSamplerData *sampler = (SystemSamplerData *) tsdesc->tsmdata;
+ OffsetNumber tupoffset = sampler->lt;
if (tupoffset == InvalidOffsetNumber)
tupoffset = FirstOffsetNumber;
@@ -136,8 +136,8 @@ tsm_system_end(PG_FUNCTION_ARGS)
Datum
tsm_system_reset(PG_FUNCTION_ARGS)
{
- TableSampleDesc *tsdesc = (TableSampleDesc *) PG_GETARG_POINTER(0);
- SystemSamplerData *sampler = (SystemSamplerData *) tsdesc->tsmdata;
+ TableSampleDesc *tsdesc = (TableSampleDesc *) PG_GETARG_POINTER(0);
+ SystemSamplerData *sampler = (SystemSamplerData *) tsdesc->tsmdata;
sampler->lt = InvalidOffsetNumber;
BlockSampler_Init(&sampler->bs, sampler->nblocks, sampler->samplesize,
@@ -152,14 +152,14 @@ tsm_system_reset(PG_FUNCTION_ARGS)
Datum
tsm_system_cost(PG_FUNCTION_ARGS)
{
- PlannerInfo *root = (PlannerInfo *) PG_GETARG_POINTER(0);
- Path *path = (Path *) PG_GETARG_POINTER(1);
- RelOptInfo *baserel = (RelOptInfo *) PG_GETARG_POINTER(2);
- List *args = (List *) PG_GETARG_POINTER(3);
- BlockNumber *pages = (BlockNumber *) PG_GETARG_POINTER(4);
- double *tuples = (double *) PG_GETARG_POINTER(5);
- Node *pctnode;
- float4 samplesize;
+ PlannerInfo *root = (PlannerInfo *) PG_GETARG_POINTER(0);
+ Path *path = (Path *) PG_GETARG_POINTER(1);
+ RelOptInfo *baserel = (RelOptInfo *) PG_GETARG_POINTER(2);
+ List *args = (List *) PG_GETARG_POINTER(3);
+ BlockNumber *pages = (BlockNumber *) PG_GETARG_POINTER(4);
+ double *tuples = (double *) PG_GETARG_POINTER(5);
+ Node *pctnode;
+ float4 samplesize;
pctnode = linitial(args);
pctnode = estimate_expression_value(root, pctnode);
diff --git a/src/backend/access/tablesample/tablesample.c b/src/backend/access/tablesample/tablesample.c
index ef55d062e75..3398d02f854 100644
--- a/src/backend/access/tablesample/tablesample.c
+++ b/src/backend/access/tablesample/tablesample.c
@@ -1,14 +1,14 @@
/*-------------------------------------------------------------------------
*
* tablesample.c
- * TABLESAMPLE internal API
+ * TABLESAMPLE internal API
*
* Portions Copyright (c) 1996-2015, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
- * src/backend/access/tablesample/tablesample.c
+ * src/backend/access/tablesample/tablesample.c
*
* TABLESAMPLE is the SQL standard clause for sampling the relations.
*
@@ -53,7 +53,7 @@ tablesample_init(SampleScanState *scanstate, TableSampleClause *tablesample)
List *args = tablesample->args;
ListCell *arg;
ExprContext *econtext = scanstate->ss.ps.ps_ExprContext;
- TableSampleDesc *tsdesc = (TableSampleDesc *) palloc0(sizeof(TableSampleDesc));
+ TableSampleDesc *tsdesc = (TableSampleDesc *) palloc0(sizeof(TableSampleDesc));
/* Load functions */
fmgr_info(tablesample->tsminit, &(tsdesc->tsminit));
@@ -78,21 +78,21 @@ tablesample_init(SampleScanState *scanstate, TableSampleClause *tablesample)
fcinfo.argnull[0] = false;
/*
- * Second arg for init function is always REPEATABLE
- * When tablesample->repeatable is NULL then REPEATABLE clause was not
- * specified.
- * When specified, the expression cannot evaluate to NULL.
+ * Second arg for init function is always REPEATABLE When
+ * tablesample->repeatable is NULL then REPEATABLE clause was not
+ * specified. When specified, the expression cannot evaluate to NULL.
*/
if (tablesample->repeatable)
{
ExprState *argstate = ExecInitExpr((Expr *) tablesample->repeatable,
(PlanState *) scanstate);
+
fcinfo.arg[1] = ExecEvalExpr(argstate, econtext,
&fcinfo.argnull[1], NULL);
if (fcinfo.argnull[1])
ereport(ERROR,
(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
- errmsg("REPEATABLE clause must be NOT NULL numeric value")));
+ errmsg("REPEATABLE clause must be NOT NULL numeric value")));
}
else
{
@@ -130,15 +130,15 @@ tablesample_init(SampleScanState *scanstate, TableSampleClause *tablesample)
HeapTuple
tablesample_getnext(TableSampleDesc *desc)
{
- HeapScanDesc scan = desc->heapScan;
- HeapTuple tuple = &(scan->rs_ctup);
- bool pagemode = scan->rs_pageatatime;
- BlockNumber blockno;
- Page page;
- bool page_all_visible;
- ItemId itemid;
- OffsetNumber tupoffset,
- maxoffset;
+ HeapScanDesc scan = desc->heapScan;
+ HeapTuple tuple = &(scan->rs_ctup);
+ bool pagemode = scan->rs_pageatatime;
+ BlockNumber blockno;
+ Page page;
+ bool page_all_visible;
+ ItemId itemid;
+ OffsetNumber tupoffset,
+ maxoffset;
if (!scan->rs_inited)
{
@@ -152,7 +152,7 @@ tablesample_getnext(TableSampleDesc *desc)
return NULL;
}
blockno = DatumGetInt32(FunctionCall1(&desc->tsmnextblock,
- PointerGetDatum(desc)));
+ PointerGetDatum(desc)));
if (!BlockNumberIsValid(blockno))
{
tuple->t_data = NULL;
@@ -184,14 +184,14 @@ tablesample_getnext(TableSampleDesc *desc)
CHECK_FOR_INTERRUPTS();
tupoffset = DatumGetUInt16(FunctionCall3(&desc->tsmnexttuple,
- PointerGetDatum(desc),
- UInt32GetDatum(blockno),
- UInt16GetDatum(maxoffset)));
+ PointerGetDatum(desc),
+ UInt32GetDatum(blockno),
+ UInt16GetDatum(maxoffset)));
if (OffsetNumberIsValid(tupoffset))
{
- bool visible;
- bool found;
+ bool visible;
+ bool found;
/* Skip invalid tuple pointers. */
itemid = PageGetItemId(page, tupoffset);
@@ -208,8 +208,8 @@ tablesample_getnext(TableSampleDesc *desc)
visible = SampleTupleVisible(tuple, tupoffset, scan);
/*
- * Let the sampling method examine the actual tuple and decide if we
- * should return it.
+ * Let the sampling method examine the actual tuple and decide if
+ * we should return it.
*
* Note that we let it examine even invisible tuples for
* statistical purposes, but not return them since user should
@@ -218,10 +218,10 @@ tablesample_getnext(TableSampleDesc *desc)
if (OidIsValid(desc->tsmexaminetuple.fn_oid))
{
found = DatumGetBool(FunctionCall4(&desc->tsmexaminetuple,
- PointerGetDatum(desc),
- UInt32GetDatum(blockno),
- PointerGetDatum(tuple),
- BoolGetDatum(visible)));
+ PointerGetDatum(desc),
+ UInt32GetDatum(blockno),
+ PointerGetDatum(tuple),
+ BoolGetDatum(visible)));
/* Should not happen if sampling method is well written. */
if (found && !visible)
elog(ERROR, "Sampling method wanted to return invisible tuple");
@@ -248,19 +248,19 @@ tablesample_getnext(TableSampleDesc *desc)
LockBuffer(scan->rs_cbuf, BUFFER_LOCK_UNLOCK);
blockno = DatumGetInt32(FunctionCall1(&desc->tsmnextblock,
- PointerGetDatum(desc)));
+ PointerGetDatum(desc)));
/*
- * Report our new scan position for synchronization purposes. We
- * don't do that when moving backwards, however. That would just
- * mess up any other forward-moving scanners.
+ * Report our new scan position for synchronization purposes. We don't
+ * do that when moving backwards, however. That would just mess up any
+ * other forward-moving scanners.
*
- * Note: we do this before checking for end of scan so that the
- * final state of the position hint is back at the start of the
- * rel. That's not strictly necessary, but otherwise when you run
- * the same query multiple times the starting position would shift
- * a little bit backwards on every invocation, which is confusing.
- * We don't guarantee any specific ordering in general, though.
+ * Note: we do this before checking for end of scan so that the final
+ * state of the position hint is back at the start of the rel. That's
+ * not strictly necessary, but otherwise when you run the same query
+ * multiple times the starting position would shift a little bit
+ * backwards on every invocation, which is confusing. We don't
+ * guarantee any specific ordering in general, though.
*/
if (scan->rs_syncscan)
ss_report_location(scan->rs_rd, BlockNumberIsValid(blockno) ?
@@ -321,25 +321,25 @@ SampleTupleVisible(HeapTuple tuple, OffsetNumber tupoffset, HeapScanDesc scan)
{
/*
* If this scan is reading whole pages at a time, there is already
- * visibility info present in rs_vistuples so we can just search it
- * for the tupoffset.
+ * visibility info present in rs_vistuples so we can just search it for
+ * the tupoffset.
*/
if (scan->rs_pageatatime)
{
- int start = 0,
- end = scan->rs_ntuples - 1;
+ int start = 0,
+ end = scan->rs_ntuples - 1;
/*
* Do the binary search over rs_vistuples, it's already sorted by
* OffsetNumber so we don't need to do any sorting ourselves here.
*
- * We could use bsearch() here but it's slower for integers because
- * of the function call overhead and because it needs boiler plate code
+ * We could use bsearch() here but it's slower for integers because of
+ * the function call overhead and because it needs boiler plate code
* it would not save us anything code-wise anyway.
*/
while (start <= end)
{
- int mid = start + (end - start) / 2;
+ int mid = start + (end - start) / 2;
OffsetNumber curoffset = scan->rs_vistuples[mid];
if (curoffset == tupoffset)
@@ -358,7 +358,7 @@ SampleTupleVisible(HeapTuple tuple, OffsetNumber tupoffset, HeapScanDesc scan)
Snapshot snapshot = scan->rs_snapshot;
Buffer buffer = scan->rs_cbuf;
- bool visible = HeapTupleSatisfiesVisibility(tuple, snapshot, buffer);
+ bool visible = HeapTupleSatisfiesVisibility(tuple, snapshot, buffer);
CheckForSerializableConflictOut(visible, scan->rs_rd, tuple, buffer,
snapshot);
generated by cgit v1.2.3 (git 2.39.1) at 2025-07-09 02:35:24 +0000