diff options
Diffstat (limited to 'src/backend/commands/analyze.c')
| -rw-r--r-- | src/backend/commands/analyze.c | 42 |
1 files changed, 26 insertions, 16 deletions
diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c index da27a13a3f0..516b43b0e34 100644 --- a/src/backend/commands/analyze.c +++ b/src/backend/commands/analyze.c @@ -76,6 +76,8 @@ int default_statistics_target = 100; /* A few variables that don't seem worth passing around as parameters */ static MemoryContext anl_context = NULL; static BufferAccessStrategy vac_strategy; +static ScanAnalyzeNextBlockFunc scan_analyze_next_block; +static ScanAnalyzeNextTupleFunc scan_analyze_next_tuple; static void do_analyze_rel(Relation onerel, @@ -88,9 +90,6 @@ static void compute_index_stats(Relation onerel, double totalrows, MemoryContext col_context); static VacAttrStats *examine_attribute(Relation onerel, int attnum, Node *index_expr); -static int acquire_sample_rows(Relation onerel, int elevel, - HeapTuple *rows, int targrows, - double *totalrows, double *totaldeadrows); static int compare_rows(const void *a, const void *b, void *arg); static int acquire_inherited_sample_rows(Relation onerel, int elevel, HeapTuple *rows, int targrows, @@ -191,7 +190,10 @@ analyze_rel(Oid relid, RangeVar *relation, if (onerel->rd_rel->relkind == RELKIND_RELATION || onerel->rd_rel->relkind == RELKIND_MATVIEW) { - /* Use row acquisition function provided by table AM */ + /* + * Get row acquisition function, blocks and tuples iteration callbacks + * provided by table AM + */ table_relation_analyze(onerel, &acquirefunc, &relpages, vac_strategy); } @@ -1117,15 +1119,17 @@ block_sampling_read_stream_next(ReadStream *stream, } /* - * acquire_sample_rows -- acquire a random sample of rows from the heap + * acquire_sample_rows -- acquire a random sample of rows from the + * block-based relation * * Selected rows are returned in the caller-allocated array rows[], which * must have at least targrows entries. * The actual number of rows selected is returned as the function result. - * We also estimate the total numbers of live and dead rows in the heap, + * We also estimate the total numbers of live and dead rows in the relation, * and return them into *totalrows and *totaldeadrows, respectively. * - * The returned list of tuples is in order by physical position in the heap. + * The returned list of tuples is in order by physical position in the + * relation. * (We will rely on this later to derive correlation estimates.) * * As of May 2004 we use a new two-stage method: Stage one selects up @@ -1147,7 +1151,7 @@ block_sampling_read_stream_next(ReadStream *stream, * look at a statistically unbiased set of blocks, we should get * unbiased estimates of the average numbers of live and dead rows per * block. The previous sampling method put too much credence in the row - * density near the start of the heap. + * density near the start of the relation. */ static int acquire_sample_rows(Relation onerel, int elevel, @@ -1188,7 +1192,7 @@ acquire_sample_rows(Relation onerel, int elevel, /* Prepare for sampling rows */ reservoir_init_selection_state(&rstate, targrows); - scan = heap_beginscan(onerel, NULL, 0, NULL, NULL, SO_TYPE_ANALYZE); + scan = table_beginscan_analyze(onerel); slot = table_slot_create(onerel, NULL); stream = read_stream_begin_relation(READ_STREAM_MAINTENANCE, @@ -1200,11 +1204,11 @@ acquire_sample_rows(Relation onerel, int elevel, 0); /* Outer loop over blocks to sample */ - while (heapam_scan_analyze_next_block(scan, stream)) + while (scan_analyze_next_block(scan, stream)) { vacuum_delay_point(); - while (heapam_scan_analyze_next_tuple(scan, OldestXmin, &liverows, &deadrows, slot)) + while (scan_analyze_next_tuple(scan, OldestXmin, &liverows, &deadrows, slot)) { /* * The first targrows sample rows are simply copied into the @@ -1256,7 +1260,7 @@ acquire_sample_rows(Relation onerel, int elevel, read_stream_end(stream); ExecDropSingleTupleTableSlot(slot); - heap_endscan(scan); + table_endscan(scan); /* * If we didn't find as many tuples as we wanted then we're done. No sort @@ -1328,16 +1332,22 @@ compare_rows(const void *a, const void *b, void *arg) } /* - * heapam_analyze -- implementation of relation_analyze() table access method - * callback for heap + * block_level_table_analyze -- implementation of relation_analyze() for + * block-level table access methods */ void -heapam_analyze(Relation relation, AcquireSampleRowsFunc *func, - BlockNumber *totalpages, BufferAccessStrategy bstrategy) +block_level_table_analyze(Relation relation, + AcquireSampleRowsFunc *func, + BlockNumber *totalpages, + BufferAccessStrategy bstrategy, + ScanAnalyzeNextBlockFunc scan_analyze_next_block_cb, + ScanAnalyzeNextTupleFunc scan_analyze_next_tuple_cb) { *func = acquire_sample_rows; *totalpages = RelationGetNumberOfBlocks(relation); vac_strategy = bstrategy; + scan_analyze_next_block = scan_analyze_next_block_cb; + scan_analyze_next_tuple = scan_analyze_next_tuple_cb; } |