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 1.65 2006/07/31 20:09:05 tgl Exp $
  11  *
  12  *-------------------------------------------------------------------------
  13  */
  14 #ifndef GENAM_H
  15 #define GENAM_H
  16
  17 #include "access/relscan.h"
  18 #include "access/sdir.h"
  19 #include "nodes/primnodes.h"
  20 #include "storage/lock.h"
  21
  22 /*
  23  * Struct for statistics returned by ambuild
  24  */
  25 typedef struct IndexBuildResult
  26 {
  27         double          heap_tuples;    /* # of tuples seen in parent table */
  28         double          index_tuples;   /* # of tuples inserted into index */
  29 } IndexBuildResult;
  30
  31 /*
  32  * Struct for input arguments passed to ambulkdelete and amvacuumcleanup
  33  *
  34  * Note that num_heap_tuples will not be valid during ambulkdelete,
  35  * only amvacuumcleanup.
  36  */
  37 typedef struct IndexVacuumInfo
  38 {
  39         Relation        index;                  /* the index being vacuumed */
  40         bool            vacuum_full;    /* VACUUM FULL (we have exclusive lock) */
  41         int                     message_level;  /* ereport level for progress messages */
  42         double          num_heap_tuples;        /* tuples remaining in heap */
  43 } IndexVacuumInfo;
  44
  45 /*
  46  * Struct for statistics returned by ambulkdelete and amvacuumcleanup
  47  *
  48  * This struct is normally allocated by the first ambulkdelete call and then
  49  * passed along through subsequent ones until amvacuumcleanup; however,
  50  * amvacuumcleanup must be prepared to allocate it in the case where no
  51  * ambulkdelete calls were made (because no tuples needed deletion).
  52  * Note that an index AM could choose to return a larger struct
  53  * of which this is just the first field; this provides a way for ambulkdelete
  54  * to communicate additional private data to amvacuumcleanup.
  55  *
  56  * Note: pages_removed is the amount by which the index physically shrank,
  57  * if any (ie the change in its total size on disk).  pages_deleted and
  58  * pages_free refer to free space within the index file.
  59  */
  60 typedef struct IndexBulkDeleteResult
  61 {
  62         BlockNumber num_pages;          /* pages remaining in index */
  63         BlockNumber pages_removed;      /* # removed during vacuum operation */
  64         double          num_index_tuples;               /* tuples remaining */
  65         double          tuples_removed; /* # removed during vacuum operation */
  66         BlockNumber pages_deleted;      /* # unused pages in index */
  67         BlockNumber pages_free;         /* # pages available for reuse */
  68 } IndexBulkDeleteResult;
  69
  70 /* Typedef for callback function to determine if a tuple is bulk-deletable */
  71 typedef bool (*IndexBulkDeleteCallback) (ItemPointer itemptr, void *state);
  72
  73 /* Struct for heap-or-index scans of system tables */
  74 typedef struct SysScanDescData
  75 {
  76         Relation        heap_rel;               /* catalog being scanned */
  77         Relation        irel;                   /* NULL if doing heap scan */
  78         HeapScanDesc scan;                      /* only valid in heap-scan case */
  79         IndexScanDesc iscan;            /* only valid in index-scan case */
  80 } SysScanDescData;
  81
  82 typedef SysScanDescData *SysScanDesc;
  83
  84
  85 /*
  86  * generalized index_ interface routines (in indexam.c)
  87  */
  88 extern Relation index_open(Oid relationId, LOCKMODE lockmode);
  89 extern void index_close(Relation relation, LOCKMODE lockmode);
  90
  91 extern bool index_insert(Relation indexRelation,
  92                          Datum *values, bool *isnull,
  93                          ItemPointer heap_t_ctid,
  94                          Relation heapRelation,
  95                          bool check_uniqueness);
  96
  97 extern IndexScanDesc index_beginscan(Relation heapRelation,
  98                                 Relation indexRelation,
  99                                 Snapshot snapshot,
 100                                 int nkeys, ScanKey key);
 101 extern IndexScanDesc index_beginscan_multi(Relation indexRelation,
 102                                           Snapshot snapshot,
 103                                           int nkeys, ScanKey key);
 104 extern void index_rescan(IndexScanDesc scan, ScanKey key);
 105 extern void index_endscan(IndexScanDesc scan);
 106 extern void index_markpos(IndexScanDesc scan);
 107 extern void index_restrpos(IndexScanDesc scan);
 108 extern HeapTuple index_getnext(IndexScanDesc scan, ScanDirection direction);
 109 extern bool index_getnext_indexitem(IndexScanDesc scan,
 110                                                 ScanDirection direction);
 111 extern bool index_getmulti(IndexScanDesc scan,
 112                            ItemPointer tids, int32 max_tids,
 113                            int32 *returned_tids);
 114
 115 extern IndexBulkDeleteResult *index_bulk_delete(IndexVacuumInfo *info,
 116                                   IndexBulkDeleteResult *stats,
 117                                   IndexBulkDeleteCallback callback,
 118                                   void *callback_state);
 119 extern IndexBulkDeleteResult *index_vacuum_cleanup(IndexVacuumInfo *info,
 120                                          IndexBulkDeleteResult *stats);
 121 extern RegProcedure index_getprocid(Relation irel, AttrNumber attnum,
 122                                 uint16 procnum);
 123 extern FmgrInfo *index_getprocinfo(Relation irel, AttrNumber attnum,
 124                                   uint16 procnum);
 125
 126 /*
 127  * index access method support routines (in genam.c)
 128  */
 129 extern IndexScanDesc RelationGetIndexScan(Relation indexRelation,
 130                                          int nkeys, ScanKey key);
 131 extern void IndexScanEnd(IndexScanDesc scan);
 132
 133 /*
 134  * heap-or-index access to system catalogs (in genam.c)
 135  */
 136 extern SysScanDesc systable_beginscan(Relation heapRelation,
 137                                    Oid indexId,
 138                                    bool indexOK,
 139                                    Snapshot snapshot,
 140                                    int nkeys, ScanKey key);
 141 extern HeapTuple systable_getnext(SysScanDesc sysscan);
 142 extern void systable_endscan(SysScanDesc sysscan);
 143
 144 #endif   /* GENAM_H */