src/include/utils/rel.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * rel.h
   4  *        POSTGRES relation descriptor (a/k/a relcache entry) definitions.
   5  *
   6  *
   7  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
   8  * Portions Copyright (c) 1994, Regents of the University of California
   9  *
  10  * $Id: rel.h,v 1.64 2002/11/23 03:59:09 momjian Exp $
  11  *
  12  *-------------------------------------------------------------------------
  13  */
  14 #ifndef REL_H
  15 #define REL_H
  16
  17 #include "access/strat.h"
  18 #include "access/tupdesc.h"
  19 #include "catalog/pg_am.h"
  20 #include "catalog/pg_class.h"
  21 #include "catalog/pg_index.h"
  22 #include "rewrite/prs2lock.h"
  23 #include "storage/block.h"
  24 #include "storage/fd.h"
  25 #include "storage/relfilenode.h"
  26
  27
  28 /*
  29  * LockRelId and LockInfo really belong to lmgr.h, but it's more convenient
  30  * to declare them here so we can have a LockInfoData field in a Relation.
  31  */
  32
  33 typedef struct LockRelId
  34 {
  35         Oid                     relId;                  /* a relation identifier */
  36         Oid                     dbId;                   /* a database identifier */
  37 } LockRelId;
  38
  39 typedef struct LockInfoData
  40 {
  41         LockRelId       lockRelId;
  42 } LockInfoData;
  43
  44 typedef LockInfoData *LockInfo;
  45
  46 /*
  47  * Likewise, this struct really belongs to trigger.h, but for convenience
  48  * we put it here.
  49  */
  50 typedef struct Trigger
  51 {
  52         Oid                     tgoid;                  /* OID of trigger (pg_trigger row) */
  53         /* Remaining fields are copied from pg_trigger, see pg_trigger.h */
  54         char       *tgname;
  55         Oid                     tgfoid;
  56         int16           tgtype;
  57         bool            tgenabled;
  58         bool            tgisconstraint;
  59         Oid                     tgconstrrelid;
  60         bool            tgdeferrable;
  61         bool            tginitdeferred;
  62         int16           tgnargs;
  63         int16           tgattr[FUNC_MAX_ARGS];
  64         char      **tgargs;
  65 } Trigger;
  66
  67 typedef struct TriggerDesc
  68 {
  69         /*
  70          * Index data to identify which triggers are which.  Since each
  71          * trigger can appear in more than one class, for each class we
  72          * provide a list of integer indexes into the triggers array.
  73          */
  74 #define TRIGGER_NUM_EVENT_CLASSES  3
  75
  76         uint16          n_before_statement[TRIGGER_NUM_EVENT_CLASSES];
  77         uint16          n_before_row[TRIGGER_NUM_EVENT_CLASSES];
  78         uint16          n_after_row[TRIGGER_NUM_EVENT_CLASSES];
  79         uint16          n_after_statement[TRIGGER_NUM_EVENT_CLASSES];
  80         int                *tg_before_statement[TRIGGER_NUM_EVENT_CLASSES];
  81         int                *tg_before_row[TRIGGER_NUM_EVENT_CLASSES];
  82         int                *tg_after_row[TRIGGER_NUM_EVENT_CLASSES];
  83         int                *tg_after_statement[TRIGGER_NUM_EVENT_CLASSES];
  84
  85         /* The actual array of triggers is here */
  86         Trigger    *triggers;
  87         int                     numtriggers;
  88 } TriggerDesc;
  89
  90
  91 /* ----------
  92  * Same for the statistics collector data in Relation and scan data.
  93  * ----------
  94  */
  95 typedef struct PgStat_Info
  96 {
  97         void       *tabentry;
  98         bool            no_stats;
  99         bool            heap_scan_counted;
 100         bool            index_scan_counted;
 101 } PgStat_Info;
 102
 103 /*
 104  * Here are the contents of a relation cache entry.
 105  */
 106
 107 typedef struct RelationData
 108 {
 109         File            rd_fd;                  /* open file descriptor, or -1 if none */
 110         RelFileNode rd_node;            /* file node (physical identifier) */
 111         BlockNumber rd_nblocks;         /* number of blocks in rel */
 112         BlockNumber rd_targblock;       /* current insertion target block, or
 113                                                                  * InvalidBlockNumber */
 114         int                     rd_refcnt;              /* reference count */
 115         bool            rd_isnew;               /* rel was created in current xact */
 116
 117         /*
 118          * NOTE: rd_isnew should be relied on only for optimization purposes;
 119          * it is possible for new-ness to be "forgotten" (eg, after CLUSTER).
 120          */
 121         bool            rd_istemp;              /* rel uses the local buffer mgr */
 122         bool            rd_isnailed;    /* rel is nailed in cache */
 123         bool            rd_indexfound;  /* true if rd_indexlist is valid */
 124         Form_pg_class rd_rel;           /* RELATION tuple */
 125         TupleDesc       rd_att;                 /* tuple descriptor */
 126         Oid                     rd_id;                  /* relation's object id */
 127         List       *rd_indexlist;       /* list of OIDs of indexes on relation */
 128         LockInfoData rd_lockInfo;       /* lock mgr's info for locking relation */
 129         RuleLock   *rd_rules;           /* rewrite rules */
 130         MemoryContext rd_rulescxt;      /* private memory cxt for rd_rules, if any */
 131         TriggerDesc *trigdesc;          /* Trigger info, or NULL if rel has none */
 132
 133         /* These are non-NULL only for an index relation: */
 134         Form_pg_index rd_index;         /* pg_index tuple describing this index */
 135         Form_pg_am      rd_am;                  /* pg_am tuple for index's AM */
 136
 137         /* index access support info (used only for an index relation) */
 138         MemoryContext rd_indexcxt;      /* private memory cxt for this stuff */
 139         IndexStrategy rd_istrat;        /* operator strategy map */
 140         Oid                *rd_operator;        /* OIDs of index operators */
 141         RegProcedure *rd_support;       /* OIDs of support procedures */
 142         struct FmgrInfo *rd_supportinfo;        /* lookup info for support
 143                                                                                  * procedures */
 144         /* "struct FmgrInfo" avoids need to include fmgr.h here */
 145
 146         /* statistics collection area */
 147         PgStat_Info pgstat_info;
 148 } RelationData;
 149
 150 typedef RelationData *Relation;
 151
 152
 153 /* ----------------
 154  *              RelationPtr is used in the executor to support index scans
 155  *              where we have to keep track of several index relations in an
 156  *              array.  -cim 9/10/89
 157  * ----------------
 158  */
 159 typedef Relation *RelationPtr;
 160
 161
 162 /*
 163  * RelationIsValid
 164  *              True iff relation descriptor is valid.
 165  */
 166 #define RelationIsValid(relation) PointerIsValid(relation)
 167
 168 #define InvalidRelation ((Relation) NULL)
 169
 170 /*
 171  * RelationHasReferenceCountZero
 172  *              True iff relation reference count is zero.
 173  *
 174  * Note:
 175  *              Assumes relation descriptor is valid.
 176  */
 177 #define RelationHasReferenceCountZero(relation) \
 178                 ((bool)((relation)->rd_refcnt == 0))
 179
 180 /*
 181  * RelationSetReferenceCount
 182  *              Sets relation reference count.
 183  */
 184 #define RelationSetReferenceCount(relation,count) \
 185         ((relation)->rd_refcnt = (count))
 186
 187 /*
 188  * RelationIncrementReferenceCount
 189  *              Increments relation reference count.
 190  */
 191 #define RelationIncrementReferenceCount(relation) \
 192         ((relation)->rd_refcnt += 1)
 193
 194 /*
 195  * RelationDecrementReferenceCount
 196  *              Decrements relation reference count.
 197  */
 198 #define RelationDecrementReferenceCount(relation) \
 199         (AssertMacro((relation)->rd_refcnt > 0), \
 200          (relation)->rd_refcnt -= 1)
 201
 202 /*
 203  * RelationGetForm
 204  *              Returns pg_class tuple for a relation.
 205  *
 206  * Note:
 207  *              Assumes relation descriptor is valid.
 208  */
 209 #define RelationGetForm(relation) ((relation)->rd_rel)
 210
 211 /*
 212  * RelationGetRelid
 213  *
 214  *      returns the OID of the relation
 215  */
 216 #define RelationGetRelid(relation) ((relation)->rd_id)
 217
 218 /*
 219  * RelationGetFile
 220  *
 221  *        Returns the open file descriptor for the rel
 222  */
 223 #define RelationGetFile(relation) ((relation)->rd_fd)
 224
 225 /*
 226  * RelationGetNumberOfAttributes
 227  *
 228  *        Returns the number of attributes.
 229  */
 230 #define RelationGetNumberOfAttributes(relation) ((relation)->rd_rel->relnatts)
 231
 232 /*
 233  * RelationGetDescr
 234  *              Returns tuple descriptor for a relation.
 235  */
 236 #define RelationGetDescr(relation) ((relation)->rd_att)
 237
 238 /*
 239  * RelationGetIndexStrategy
 240  *              Returns index strategy for a relation.
 241  *
 242  * Note:
 243  *              Assumes relation descriptor is valid.
 244  *              Assumes relation descriptor is for an index relation.
 245  */
 246 #define RelationGetIndexStrategy(relation) ((relation)->rd_istrat)
 247
 248 /*
 249  * RelationGetRelationName
 250  *
 251  *        Returns the rel's name.
 252  *
 253  * Note that the name is only unique within the containing namespace.
 254  */
 255 #define RelationGetRelationName(relation) \
 256         (NameStr((relation)->rd_rel->relname))
 257
 258 /*
 259  * RelationGetNamespace
 260  *
 261  *        Returns the rel's namespace OID.
 262  */
 263 #define RelationGetNamespace(relation) \
 264         ((relation)->rd_rel->relnamespace)
 265
 266 #endif   /* REL_H */