diff options
Diffstat (limited to 'src/include/access/relscan.h')
| -rw-r--r-- | src/include/access/relscan.h | 122 |
1 files changed, 68 insertions, 54 deletions
diff --git a/src/include/access/relscan.h b/src/include/access/relscan.h index b78ef2f47d0..82de4cdcf2c 100644 --- a/src/include/access/relscan.h +++ b/src/include/access/relscan.h @@ -21,63 +21,76 @@ #include "storage/spin.h" #include "utils/relcache.h" + +struct ParallelTableScanDescData; + /* - * Shared state for parallel heap scan. - * - * Each backend participating in a parallel heap scan has its own - * HeapScanDesc in backend-private memory, and those objects all contain - * a pointer to this structure. The information here must be sufficient - * to properly initialize each new HeapScanDesc as workers join the scan, - * and it must act as a font of block numbers for those workers. + * Generic descriptor for table scans. This is the base-class for table scans, + * which needs to be embedded in the scans of individual AMs. */ -typedef struct ParallelHeapScanDescData -{ - Oid phs_relid; /* OID of relation to scan */ - bool phs_syncscan; /* report location to syncscan logic? */ - BlockNumber phs_nblocks; /* # blocks in relation at start of scan */ - slock_t phs_mutex; /* mutual exclusion for setting startblock */ - BlockNumber phs_startblock; /* starting block number */ - pg_atomic_uint64 phs_nallocated; /* number of blocks allocated to - * workers so far. */ - bool phs_snapshot_any; /* SnapshotAny, not phs_snapshot_data? */ - char phs_snapshot_data[FLEXIBLE_ARRAY_MEMBER]; -} ParallelHeapScanDescData; - -typedef struct HeapScanDescData +typedef struct TableScanDescData { /* scan parameters */ Relation rs_rd; /* heap relation descriptor */ struct SnapshotData *rs_snapshot; /* snapshot to see */ int rs_nkeys; /* number of scan keys */ - struct ScanKeyData *rs_key; /* array of scan key descriptors */ + struct ScanKeyData *rs_key; /* array of scan key descriptors */ bool rs_bitmapscan; /* true if this is really a bitmap scan */ bool rs_samplescan; /* true if this is really a sample scan */ bool rs_pageatatime; /* verify visibility page-at-a-time? */ bool rs_allow_strat; /* allow or disallow use of access strategy */ bool rs_allow_sync; /* allow or disallow use of syncscan */ bool rs_temp_snap; /* unregister snapshot at scan end? */ - - /* state set up at initscan time */ - BlockNumber rs_nblocks; /* total number of blocks in rel */ - BlockNumber rs_startblock; /* block # to start at */ - BlockNumber rs_numblocks; /* max number of blocks to scan */ - /* rs_numblocks is usually InvalidBlockNumber, meaning "scan whole rel" */ - BufferAccessStrategy rs_strategy; /* access strategy for reads */ bool rs_syncscan; /* report location to syncscan logic? */ - /* scan current state */ - bool rs_inited; /* false = scan not init'd yet */ - HeapTupleData rs_ctup; /* current tuple in scan, if any */ - BlockNumber rs_cblock; /* current block # in scan, if any */ - Buffer rs_cbuf; /* current buffer in scan, if any */ - /* NB: if rs_cbuf is not InvalidBuffer, we hold a pin on that buffer */ - struct ParallelHeapScanDescData *rs_parallel; /* parallel scan information */ + struct ParallelTableScanDescData *rs_parallel; /* parallel scan + * information */ - /* these fields only used in page-at-a-time mode and for bitmap scans */ - int rs_cindex; /* current tuple's index in vistuples */ - int rs_ntuples; /* number of visible tuples on page */ - OffsetNumber rs_vistuples[MaxHeapTuplesPerPage]; /* their offsets */ -} HeapScanDescData; +} TableScanDescData; +typedef struct TableScanDescData *TableScanDesc; + +/* + * Shared state for parallel table scan. + * + * Each backend participating in a parallel table scan has its own + * TableScanDesc in backend-private memory, and those objects all contain a + * pointer to this structure. The information here must be sufficient to + * properly initialize each new TableScanDesc as workers join the scan, and it + * must act as a information what to scan for those workers. + */ +typedef struct ParallelTableScanDescData +{ + Oid phs_relid; /* OID of relation to scan */ + bool phs_syncscan; /* report location to syncscan logic? */ + bool phs_snapshot_any; /* SnapshotAny, not phs_snapshot_data? */ + Size phs_snapshot_off; /* data for snapshot */ +} ParallelTableScanDescData; +typedef struct ParallelTableScanDescData *ParallelTableScanDesc; + +/* + * Shared state for parallel table scans, for block oriented storage. + */ +typedef struct ParallelBlockTableScanDescData +{ + ParallelTableScanDescData base; + + BlockNumber phs_nblocks; /* # blocks in relation at start of scan */ + slock_t phs_mutex; /* mutual exclusion for setting startblock */ + BlockNumber phs_startblock; /* starting block number */ + pg_atomic_uint64 phs_nallocated; /* number of blocks allocated to + * workers so far. */ +} ParallelBlockTableScanDescData; +typedef struct ParallelBlockTableScanDescData *ParallelBlockTableScanDesc; + +/* + * Base class for fetches from a table via an index. This is the base-class + * for such scans, which needs to be embedded in the respective struct for + * individual AMs. + */ +typedef struct IndexFetchTableData +{ + Relation rel; +} IndexFetchTableData; /* * We use the same IndexScanDescData structure for both amgettuple-based @@ -92,7 +105,7 @@ typedef struct IndexScanDescData struct SnapshotData *xs_snapshot; /* snapshot to see */ int numberOfKeys; /* number of index qualifier conditions */ int numberOfOrderBys; /* number of ordering operators */ - struct ScanKeyData *keyData; /* array of index qualifier descriptors */ + struct ScanKeyData *keyData; /* array of index qualifier descriptors */ struct ScanKeyData *orderByData; /* array of ordering op descriptors */ bool xs_want_itup; /* caller requests index tuples */ bool xs_temp_snap; /* unregister snapshot at scan end? */ @@ -115,12 +128,13 @@ typedef struct IndexScanDescData IndexTuple xs_itup; /* index tuple returned by AM */ struct TupleDescData *xs_itupdesc; /* rowtype descriptor of xs_itup */ HeapTuple xs_hitup; /* index data returned by AM, as HeapTuple */ - struct TupleDescData *xs_hitupdesc; /* rowtype descriptor of xs_hitup */ + struct TupleDescData *xs_hitupdesc; /* rowtype descriptor of xs_hitup */ + + ItemPointerData xs_heaptid; /* result */ + bool xs_heap_continue; /* T if must keep walking, potential + * further results */ + IndexFetchTableData *xs_heapfetch; - /* xs_ctup/xs_cbuf/xs_recheck are valid after a successful index_getnext */ - HeapTupleData xs_ctup; /* current heap tuple, if any */ - Buffer xs_cbuf; /* current heap buffer in scan, if any */ - /* NB: if xs_cbuf is not InvalidBuffer, we hold a pin on that buffer */ bool xs_recheck; /* T means scan keys must be rechecked */ /* @@ -134,9 +148,6 @@ typedef struct IndexScanDescData bool *xs_orderbynulls; bool xs_recheckorderby; - /* state data for traversing HOT chains in index_getnext */ - bool xs_continue_hot; /* T if must keep walking HOT chain */ - /* parallel index scan information, in shared memory */ struct ParallelIndexScanDescData *parallel_scan; } IndexScanDescData; @@ -150,14 +161,17 @@ typedef struct ParallelIndexScanDescData char ps_snapshot_data[FLEXIBLE_ARRAY_MEMBER]; } ParallelIndexScanDescData; -/* Struct for heap-or-index scans of system tables */ +struct TupleTableSlot; + +/* Struct for storage-or-index scans of system tables */ typedef struct SysScanDescData { Relation heap_rel; /* catalog being scanned */ Relation irel; /* NULL if doing heap scan */ - struct HeapScanDescData *scan; /* only valid in heap-scan case */ - struct IndexScanDescData *iscan; /* only valid in index-scan case */ - struct SnapshotData *snapshot; /* snapshot to unregister at end of scan */ + struct TableScanDescData *scan; /* only valid in storage-scan case */ + struct IndexScanDescData *iscan; /* only valid in index-scan case */ + struct SnapshotData *snapshot; /* snapshot to unregister at end of scan */ + struct TupleTableSlot *slot; } SysScanDescData; #endif /* RELSCAN_H */ |