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 1.27 1999/09/29 16:06:28 wieck Exp $
  10  *
  11  *-------------------------------------------------------------------------
  12  */
  13 #ifndef REL_H
  14 #define REL_H
  15
  16 #include "access/strat.h"
  17 #include "access/tupdesc.h"
  18 #include "catalog/pg_am.h"
  19 #include "catalog/pg_class.h"
  20 #include "rewrite/prs2lock.h"
  21 #include "storage/fd.h"
  22
  23
  24 /*
  25  * LockRelId and LockInfo really belong to lmgr.h, but it's more convenient
  26  * to declare them here so we can have a LockInfoData field in a Relation.
  27  */
  28
  29 typedef struct LockRelId
  30 {
  31         Oid                     relId;                  /* a relation identifier */
  32         Oid                     dbId;                   /* a database identifier */
  33 } LockRelId;
  34
  35 typedef struct LockInfoData
  36 {
  37         LockRelId       lockRelId;
  38 } LockInfoData;
  39
  40 typedef LockInfoData *LockInfo;
  41
  42
  43 typedef struct Trigger
  44 {
  45         Oid                     tgoid;
  46         char       *tgname;
  47         Oid                     tgfoid;
  48         FmgrInfo        tgfunc;
  49         int16           tgtype;
  50         bool            tgenabled;
  51         bool            tgisconstraint;
  52         bool            tgdeferrable;
  53         bool            tginitdeferred;
  54         int16           tgnargs;
  55         int16           tgattr[8];
  56         char      **tgargs;
  57 } Trigger;
  58
  59 typedef struct TriggerDesc
  60 {
  61         uint16          n_before_statement[4];
  62         uint16          n_before_row[4];
  63         uint16          n_after_row[4];
  64         uint16          n_after_statement[4];
  65         Trigger   **tg_before_statement[4];
  66         Trigger   **tg_before_row[4];
  67         Trigger   **tg_after_row[4];
  68         Trigger   **tg_after_statement[4];
  69         Trigger    *triggers;
  70 } TriggerDesc;
  71
  72
  73 typedef struct RelationData
  74 {
  75         File            rd_fd;                  /* open file descriptor */
  76         int                     rd_nblocks;             /* number of blocks in rel */
  77         uint16          rd_refcnt;              /* reference count */
  78         bool            rd_myxactonly;  /* rel uses the local buffer mgr */
  79         bool            rd_isnailed;    /* rel is nailed in cache */
  80         bool            rd_isnoname;    /* rel has no name */
  81         bool            rd_nonameunlinked;              /* noname rel already unlinked */
  82         Form_pg_am      rd_am;                  /* AM tuple */
  83         Form_pg_class rd_rel;           /* RELATION tuple */
  84         Oid                     rd_id;                  /* relation's object id */
  85         LockInfoData rd_lockInfo;       /* lock manager's info for locking relation */
  86         TupleDesc       rd_att;                 /* tuple descriptor */
  87         RuleLock   *rd_rules;           /* rewrite rules */
  88         IndexStrategy rd_istrat;
  89         RegProcedure *rd_support;
  90         TriggerDesc *trigdesc;
  91 } RelationData;
  92
  93 typedef RelationData *Relation;
  94
  95
  96 /* ----------------
  97  *              RelationPtr is used in the executor to support index scans
  98  *              where we have to keep track of several index relations in an
  99  *              array.  -cim 9/10/89
 100  * ----------------
 101  */
 102 typedef Relation *RelationPtr;
 103
 104
 105 /*
 106  * RelationIsValid
 107  *              True iff relation descriptor is valid.
 108  */
 109 #define RelationIsValid(relation) PointerIsValid(relation)
 110
 111 #define InvalidRelation ((Relation) NULL)
 112
 113 /*
 114  * RelationGetSystemPort
 115  *              Returns system port of a relation.
 116  *
 117  * Note:
 118  *              Assumes relation descriptor is valid.
 119  */
 120 #define RelationGetSystemPort(relation) ((relation)->rd_fd)
 121
 122 /*
 123  * RelationHasReferenceCountZero
 124  *              True iff relation reference count is zero.
 125  *
 126  * Note:
 127  *              Assumes relation descriptor is valid.
 128  */
 129 #define RelationHasReferenceCountZero(relation) \
 130                 ((bool)((relation)->rd_refcnt == 0))
 131
 132 /*
 133  * RelationSetReferenceCount
 134  *              Sets relation reference count.
 135  */
 136 #define RelationSetReferenceCount(relation,count) ((relation)->rd_refcnt = (count))
 137
 138 /*
 139  * RelationIncrementReferenceCount
 140  *              Increments relation reference count.
 141  */
 142 #define RelationIncrementReferenceCount(relation) ((relation)->rd_refcnt += 1)
 143
 144 /*
 145  * RelationDecrementReferenceCount
 146  *              Decrements relation reference count.
 147  */
 148 #define RelationDecrementReferenceCount(relation) ((relation)->rd_refcnt -= 1)
 149
 150 /*
 151  * RelationGetForm
 152  *              Returns relation attribute values for a relation.
 153  *
 154  * Note:
 155  *              Assumes relation descriptor is valid.
 156  */
 157 #define RelationGetForm(relation) ((relation)->rd_rel)
 158
 159 /*
 160  * RelationGetRelid
 161  *
 162  *      returns the object id of the relation
 163  *
 164  */
 165 #define RelationGetRelid(relation) ((relation)->rd_id)
 166
 167 /*
 168  * RelationGetFile
 169  *
 170  *        Returns the open File decscriptor
 171  */
 172 #define RelationGetFile(relation) ((relation)->rd_fd)
 173
 174 /*
 175  * RelationGetRelationName
 176  *
 177  *        Returns a Relation Name
 178  */
 179 #define RelationGetRelationName(relation) (&(relation)->rd_rel->relname)
 180
 181 /*
 182  * RelationGetNumberOfAttributes
 183  *
 184  *        Returns the number of attributes.
 185  */
 186 #define RelationGetNumberOfAttributes(relation) ((relation)->rd_rel->relnatts)
 187
 188 /*
 189  * RelationGetDescr
 190  *              Returns tuple descriptor for a relation.
 191  */
 192 #define RelationGetDescr(relation) ((relation)->rd_att)
 193
 194
 195 extern IndexStrategy RelationGetIndexStrategy(Relation relation);
 196
 197 extern void RelationSetIndexSupport(Relation relation, IndexStrategy strategy,
 198                                                 RegProcedure *support);
 199
 200 #endif   /* REL_H */