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 1.30 1999/11/16 04:14:03 momjian 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  * LockRelId and LockInfo really belong to lmgr.h, but it's more convenient
  25  * to declare them here so we can have a LockInfoData field in a Relation.
  26  */
  27
  28 typedef struct LockRelId
  29 {
  30         Oid                     relId;                  /* a relation identifier */
  31         Oid                     dbId;                   /* a database identifier */
  32 } LockRelId;
  33
  34 typedef struct LockInfoData
  35 {
  36         LockRelId       lockRelId;
  37 } LockInfoData;
  38
  39 typedef LockInfoData *LockInfo;
  40
  41
  42 typedef struct Trigger
  43 {
  44         Oid                     tgoid;
  45         char       *tgname;
  46         Oid                     tgfoid;
  47         FmgrInfo        tgfunc;
  48         int16           tgtype;
  49         bool            tgenabled;
  50         bool            tgisconstraint;
  51         bool            tgdeferrable;
  52         bool            tginitdeferred;
  53         int16           tgnargs;
  54         int16           tgattr[8];
  55         char      **tgargs;
  56 } Trigger;
  57
  58 typedef struct TriggerDesc
  59 {
  60         uint16          n_before_statement[4];
  61         uint16          n_before_row[4];
  62         uint16          n_after_row[4];
  63         uint16          n_after_statement[4];
  64         Trigger   **tg_before_statement[4];
  65         Trigger   **tg_before_row[4];
  66         Trigger   **tg_after_row[4];
  67         Trigger   **tg_after_statement[4];
  68         Trigger    *triggers;
  69 } TriggerDesc;
  70
  71
  72 typedef struct RelationData
  73 {
  74         File            rd_fd;                  /* open file descriptor */
  75         int                     rd_nblocks;             /* number of blocks in rel */
  76         uint16          rd_refcnt;              /* reference count */
  77         bool            rd_myxactonly;  /* rel uses the local buffer mgr */
  78         bool            rd_isnailed;    /* rel is nailed in cache */
  79         bool            rd_isnoname;    /* rel has no name */
  80         bool            rd_unlinked;    /* rel already unlinked or not created yet */
  81         Form_pg_am      rd_am;                  /* AM tuple */
  82         Form_pg_class rd_rel;           /* RELATION tuple */
  83         Oid                     rd_id;                  /* relation's object id */
  84         LockInfoData rd_lockInfo;       /* lock manager's info for locking relation */
  85         TupleDesc       rd_att;                 /* tuple descriptor */
  86         RuleLock   *rd_rules;           /* rewrite rules */
  87         IndexStrategy rd_istrat;
  88         RegProcedure *rd_support;
  89         TriggerDesc *trigdesc;
  90 } RelationData;
  91
  92 typedef RelationData *Relation;
  93
  94
  95 /* ----------------
  96  *              RelationPtr is used in the executor to support index scans
  97  *              where we have to keep track of several index relations in an
  98  *              array.  -cim 9/10/89
  99  * ----------------
 100  */
 101 typedef Relation *RelationPtr;
 102
 103
 104 /*
 105  * RelationIsValid
 106  *              True iff relation descriptor is valid.
 107  */
 108 #define RelationIsValid(relation) PointerIsValid(relation)
 109
 110 #define InvalidRelation ((Relation) NULL)
 111
 112 /*
 113  * RelationGetSystemPort
 114  *              Returns system port of a relation.
 115  *
 116  * Note:
 117  *              Assumes relation descriptor is valid.
 118  */
 119 #define RelationGetSystemPort(relation) ((relation)->rd_fd)
 120
 121 /*
 122  * RelationHasReferenceCountZero
 123  *              True iff relation reference count is zero.
 124  *
 125  * Note:
 126  *              Assumes relation descriptor is valid.
 127  */
 128 #define RelationHasReferenceCountZero(relation) \
 129                 ((bool)((relation)->rd_refcnt == 0))
 130
 131 /*
 132  * RelationSetReferenceCount
 133  *              Sets relation reference count.
 134  */
 135 #define RelationSetReferenceCount(relation,count) ((relation)->rd_refcnt = (count))
 136
 137 /*
 138  * RelationIncrementReferenceCount
 139  *              Increments relation reference count.
 140  */
 141 #define RelationIncrementReferenceCount(relation) ((relation)->rd_refcnt += 1)
 142
 143 /*
 144  * RelationDecrementReferenceCount
 145  *              Decrements relation reference count.
 146  */
 147 #define RelationDecrementReferenceCount(relation) ((relation)->rd_refcnt -= 1)
 148
 149 /*
 150  * RelationGetForm
 151  *              Returns relation attribute values for a relation.
 152  *
 153  * Note:
 154  *              Assumes relation descriptor is valid.
 155  */
 156 #define RelationGetForm(relation) ((relation)->rd_rel)
 157
 158 /*
 159  * RelationGetRelid
 160  *
 161  *      returns the object id of the relation
 162  *
 163  */
 164 #define RelationGetRelid(relation) ((relation)->rd_id)
 165
 166 /*
 167  * RelationGetFile
 168  *
 169  *        Returns the open File decscriptor
 170  */
 171 #define RelationGetFile(relation) ((relation)->rd_fd)
 172
 173 /*
 174  * RelationGetRelationName
 175  *
 176  *        Returns a Relation Name
 177  */
 178 /* added to prevent circular dependency.  bjm 1999/11/15 */
 179 char       *get_temp_rel_by_physicalname(char *relname);
 180 #define RelationGetRelationName(relation) \
 181 (\
 182         (strncmp(RelationGetPhysicalRelationName(relation), \
 183          "pg_temp.", strlen("pg_temp.")) != 0) \
 184         ? \
 185                 RelationGetPhysicalRelationName(relation) \
 186         : \
 187                 get_temp_rel_by_physicalname( \
 188                         RelationGetPhysicalRelationName(relation)) \
 189 )
 190
 191
 192 /*
 193  * RelationGetPhysicalRelationName
 194  *
 195  *        Returns a Relation Name
 196  */
 197 #define RelationGetPhysicalRelationName(relation) (NameStr((relation)->rd_rel->relname))
 198
 199 /*
 200  * RelationGetNumberOfAttributes
 201  *
 202  *        Returns the number of attributes.
 203  */
 204 #define RelationGetNumberOfAttributes(relation) ((relation)->rd_rel->relnatts)
 205
 206 /*
 207  * RelationGetDescr
 208  *              Returns tuple descriptor for a relation.
 209  */
 210 #define RelationGetDescr(relation) ((relation)->rd_att)
 211
 212
 213 extern IndexStrategy RelationGetIndexStrategy(Relation relation);
 214
 215 extern void RelationSetIndexSupport(Relation relation, IndexStrategy strategy,
 216                                                 RegProcedure *support);
 217
 218 #endif   /* REL_H */