granicus.if.org Git - postgresql/blob - src/include/access/genam.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * genam.h
   4  *        POSTGRES generalized index access method definitions.
   5  *
   6  *
   7  * Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
   8  * Portions Copyright (c) 1994, Regents of the University of California
   9  *
  10  * $PostgreSQL: pgsql/src/include/access/genam.h,v 1.60 2006/05/10 23:18:39 tgl Exp $
  11  *
  12  *-------------------------------------------------------------------------
  13  */
  14 #ifndef GENAM_H
  15 #define GENAM_H
  16
  17 #include "access/itup.h"
  18 #include "access/relscan.h"
  19 #include "access/sdir.h"
  20 #include "nodes/primnodes.h"
  21
  22
  23 /*
  24  * Struct for statistics returned by ambuild
  25  */
  26 typedef struct IndexBuildResult
  27 {
  28         double          heap_tuples;    /* # of tuples seen in parent table */
  29         double          index_tuples;   /* # of tuples inserted into index */
  30 } IndexBuildResult;
  31
  32 /*
  33  * Struct for input arguments passed to ambulkdelete and amvacuumcleanup
  34  *
  35  * Note that num_heap_tuples will not be valid during ambulkdelete,
  36  * only amvacuumcleanup.
  37  */
  38 typedef struct IndexVacuumInfo
  39 {
  40         Relation        index;                  /* the index being vacuumed */
  41         bool            vacuum_full;    /* VACUUM FULL (we have exclusive lock) */
  42         int                     message_level;  /* ereport level for progress messages */
  43         double          num_heap_tuples;        /* tuples remaining in heap */
  44 } IndexVacuumInfo;
  45
  46 /*
  47  * Struct for statistics returned by ambulkdelete and amvacuumcleanup
  48  *
  49  * This struct is normally allocated by the first ambulkdelete call and then
  50  * passed along through subsequent ones until amvacuumcleanup; however,
  51  * amvacuumcleanup must be prepared to allocate it in the case where no
  52  * ambulkdelete calls were made (because no tuples needed deletion).
  53  * Note that an index AM could choose to return a larger struct
  54  * of which this is just the first field; this provides a way for ambulkdelete
  55  * to communicate additional private data to amvacuumcleanup.
  56  *
  57  * Note: pages_removed is the amount by which the index physically shrank,
  58  * if any (ie the change in its total size on disk).  pages_deleted and
  59  * pages_free refer to free space within the index file.
  60  */
  61 typedef struct IndexBulkDeleteResult
  62 {
  63         BlockNumber num_pages;          /* pages remaining in index */
  64         BlockNumber pages_removed;      /* # removed during vacuum operation */
  65         double          num_index_tuples;               /* tuples remaining */
  66         double          tuples_removed; /* # removed during vacuum operation */
  67         BlockNumber pages_deleted;      /* # unused pages in index */
  68         BlockNumber pages_free;         /* # pages available for reuse */
  69 } IndexBulkDeleteResult;
  70
  71 /* Typedef for callback function to determine if a tuple is bulk-deletable */
  72 typedef bool (*IndexBulkDeleteCallback) (ItemPointer itemptr, void *state);
  73
  74 /* Struct for heap-or-index scans of system tables */
  75 typedef struct SysScanDescData
  76 {
  77         Relation        heap_rel;               /* catalog being scanned */
  78         Relation        irel;                   /* NULL if doing heap scan */
  79         HeapScanDesc scan;                      /* only valid in heap-scan case */
  80         IndexScanDesc iscan;            /* only valid in index-scan case */
  81 } SysScanDescData;
  82
  83 typedef SysScanDescData *SysScanDesc;
  84
  85
  86 /*
  87  * generalized index_ interface routines (in indexam.c)
  88  */
  89 extern Relation index_open(Oid relationId);
  90 extern Relation index_openrv(const RangeVar *relation);
  91 extern void index_close(Relation relation);
  92 extern bool index_insert(Relation indexRelation,
  93                          Datum *values, bool *isnull,
  94                          ItemPointer heap_t_ctid,
  95                          Relation heapRelation,
  96                          bool check_uniqueness);
  97
  98 extern IndexScanDesc index_beginscan(Relation heapRelation,
  99                                 Relation indexRelation,
 100                                 bool need_index_lock,
 101                                 Snapshot snapshot,
 102                                 int nkeys, ScanKey key);
 103 extern IndexScanDesc index_beginscan_multi(Relation indexRelation,
 104                                           bool need_index_lock,
 105                                           Snapshot snapshot,
 106                                           int nkeys, ScanKey key);
 107 extern void index_rescan(IndexScanDesc scan, ScanKey key);
 108 extern void index_endscan(IndexScanDesc scan);
 109 extern void index_markpos(IndexScanDesc scan);
 110 extern void index_restrpos(IndexScanDesc scan);
 111 extern HeapTuple index_getnext(IndexScanDesc scan, ScanDirection direction);
 112 extern bool index_getnext_indexitem(IndexScanDesc scan,
 113                                                 ScanDirection direction);
 114 extern bool index_getmulti(IndexScanDesc scan,
 115                            ItemPointer tids, int32 max_tids,
 116                            int32 *returned_tids);
 117
 118 extern IndexBulkDeleteResult *index_bulk_delete(IndexVacuumInfo *info,
 119                                   IndexBulkDeleteResult *stats,
 120                                   IndexBulkDeleteCallback callback,
 121                                   void *callback_state);
 122 extern IndexBulkDeleteResult *index_vacuum_cleanup(IndexVacuumInfo *info,
 123                                          IndexBulkDeleteResult *stats);
 124 extern RegProcedure index_getprocid(Relation irel, AttrNumber attnum,
 125                                 uint16 procnum);
 126 extern FmgrInfo *index_getprocinfo(Relation irel, AttrNumber attnum,
 127                                   uint16 procnum);
 128
 129 /*
 130  * index access method support routines (in genam.c)
 131  */
 132 extern IndexScanDesc RelationGetIndexScan(Relation indexRelation,
 133                                          int nkeys, ScanKey key);
 134 extern void IndexScanEnd(IndexScanDesc scan);
 135
 136 /*
 137  * heap-or-index access to system catalogs (in genam.c)
 138  */
 139 extern SysScanDesc systable_beginscan(Relation heapRelation,
 140                                    Oid indexId,
 141                                    bool indexOK,
 142                                    Snapshot snapshot,
 143                                    int nkeys, ScanKey key);
 144 extern HeapTuple systable_getnext(SysScanDesc sysscan);
 145 extern void systable_endscan(SysScanDesc sysscan);
 146
 147 #endif   /* GENAM_H */