src/include/utils/rel.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * rel.h
   4  *        POSTGRES relation descriptor definitions.
   5  *
   6  *
   7  * Copyright (c) 1994, Regents of the University of California
   8  *
   9  * $Id: rel.h,v 1.23 1999/05/25 16:14:57 momjian Exp $
  10  *
  11  *-------------------------------------------------------------------------
  12  */
  13 #ifndef REL_H
  14 #define REL_H
  15
  16 #include <catalog/pg_am.h>
  17 #include <catalog/pg_class.h>
  18 #include <access/strat.h>
  19 #include <access/tupdesc.h>
  20 #include <rewrite/prs2lock.h>
  21 #include <storage/fd.h>
  22
  23 typedef struct Trigger
  24 {
  25         char       *tgname;
  26         Oid                     tgfoid;
  27         FmgrInfo        tgfunc;
  28         int16           tgtype;
  29         int16           tgnargs;
  30         int16           tgattr[8];
  31         char      **tgargs;
  32 } Trigger;
  33
  34 typedef struct TriggerDesc
  35 {
  36         uint16          n_before_statement[4];
  37         uint16          n_before_row[4];
  38         uint16          n_after_row[4];
  39         uint16          n_after_statement[4];
  40         Trigger   **tg_before_statement[4];
  41         Trigger   **tg_before_row[4];
  42         Trigger   **tg_after_row[4];
  43         Trigger   **tg_after_statement[4];
  44         Trigger    *triggers;
  45 } TriggerDesc;
  46
  47 typedef struct RelationData
  48 {
  49         File            rd_fd;                  /* open file descriptor */
  50         int                     rd_nblocks;             /* number of blocks in rel */
  51         uint16          rd_refcnt;              /* reference count */
  52         bool            rd_myxactonly;  /* uses the local buffer mgr */
  53         bool            rd_isnailed;    /* rel is nailed in cache */
  54         bool            rd_isnoname;    /* rel has no name */
  55         bool            rd_nonameunlinked;              /* noname rel already unlinked */
  56         Form_pg_am      rd_am;                  /* AM tuple */
  57         Form_pg_class rd_rel;           /* RELATION tuple */
  58         Oid                     rd_id;                  /* relations's object id */
  59         Pointer         lockInfo;               /* ptr. to misc. info. */
  60         TupleDesc       rd_att;                 /* tuple desciptor */
  61         RuleLock   *rd_rules;           /* rewrite rules */
  62         IndexStrategy rd_istrat;
  63         RegProcedure *rd_support;
  64         TriggerDesc *trigdesc;
  65 } RelationData;
  66
  67 typedef RelationData *Relation;
  68
  69 /* ----------------
  70  *              RelationPtr is used in the executor to support index scans
  71  *              where we have to keep track of several index relations in an
  72  *              array.  -cim 9/10/89
  73  * ----------------
  74  */
  75 typedef Relation *RelationPtr;
  76
  77 #define InvalidRelation ((Relation)NULL)
  78
  79 /*
  80  * RelationIsValid
  81  *              True iff relation descriptor is valid.
  82  */
  83 #define RelationIsValid(relation) PointerIsValid(relation)
  84
  85 /*
  86  * RelationGetSystemPort
  87  *              Returns system port of a relation.
  88  *
  89  * Note:
  90  *              Assumes relation descriptor is valid.
  91  */
  92 #define RelationGetSystemPort(relation) ((relation)->rd_fd)
  93
  94 /*
  95  * RelationGetLockInfo
  96  *              Returns the lock information structure in the reldesc
  97  *
  98  */
  99 #define RelationGetLockInfo(relation) ((relation)->lockInfo)
 100
 101 /*
 102  * RelationHasReferenceCountZero
 103  *              True iff relation reference count is zero.
 104  *
 105  * Note:
 106  *              Assumes relation descriptor is valid.
 107  */
 108 #define RelationHasReferenceCountZero(relation) \
 109                 ((bool)((relation)->rd_refcnt == 0))
 110
 111 /*
 112  * RelationSetReferenceCount
 113  *              Sets relation reference count.
 114  */
 115 #define RelationSetReferenceCount(relation,count) ((relation)->rd_refcnt = count)
 116
 117 /*
 118  * RelationIncrementReferenceCount
 119  *              Increments relation reference count.
 120  */
 121 #define RelationIncrementReferenceCount(relation) ((relation)->rd_refcnt += 1);
 122
 123 /*
 124  * RelationDecrementReferenceCount
 125  *              Decrements relation reference count.
 126  */
 127 #define RelationDecrementReferenceCount(relation) ((relation)->rd_refcnt -= 1)
 128
 129 /*
 130  * RelationGetForm
 131  *              Returns relation attribute values for a relation.
 132  *
 133  * Note:
 134  *              Assumes relation descriptor is valid.
 135  */
 136 #define RelationGetForm(relation) ((relation)->rd_rel)
 137
 138
 139 /*
 140  * RelationGetRelid
 141  *
 142  *      returns the object id of the relation
 143  *
 144  */
 145 #define RelationGetRelid(relation) ((relation)->rd_id)
 146
 147 /*
 148  * RelationGetFile
 149  *
 150  *        Returns the open File decscriptor
 151  */
 152 #define RelationGetFile(relation) ((relation)->rd_fd)
 153
 154
 155 /*
 156  * RelationGetRelationName
 157  *
 158  *        Returns a Relation Name
 159  */
 160 #define RelationGetRelationName(relation) (&(relation)->rd_rel->relname)
 161
 162 /*
 163  * RelationGetRelationName
 164  *
 165  *        Returns a the number of attributes.
 166  */
 167 #define RelationGetNumberOfAttributes(relation) ((relation)->rd_rel->relnatts)
 168
 169 /*
 170  * RelationGetDescr
 171  *              Returns tuple descriptor for a relation.
 172  *
 173  * Note:
 174  *              Assumes relation descriptor is valid.
 175  */
 176 #define RelationGetDescr(relation) ((relation)->rd_att)
 177
 178 extern IndexStrategy RelationGetIndexStrategy(Relation relation);
 179
 180 extern void RelationSetIndexSupport(Relation relation, IndexStrategy strategy,
 181                                                 RegProcedure *support);
 182
 183 #endif   /* REL_H */