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 1.62 2002/08/11 21:17:35 tgl 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  4
  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          * NOTE: rd_isnew should be relied on only for optimization purposes;
 118          * it is possible for new-ness to be "forgotten" (eg, after CLUSTER).
 119          */
 120         bool            rd_istemp;              /* rel uses the local buffer mgr */
 121         bool            rd_isnailed;    /* rel is nailed in cache */
 122         bool            rd_indexfound;  /* true if rd_indexlist is valid */
 123         Form_pg_class rd_rel;           /* RELATION tuple */
 124         TupleDesc       rd_att;                 /* tuple descriptor */
 125         Oid                     rd_id;                  /* relation's object id */
 126         List       *rd_indexlist;       /* list of OIDs of indexes on relation */
 127         LockInfoData rd_lockInfo;       /* lock mgr's info for locking relation */
 128         RuleLock   *rd_rules;           /* rewrite rules */
 129         MemoryContext rd_rulescxt;      /* private memory cxt for rd_rules, if any */
 130         TriggerDesc *trigdesc;          /* Trigger info, or NULL if rel has none */
 131
 132         /* These are non-NULL only for an index relation: */
 133         Form_pg_index rd_index;         /* pg_index tuple describing this index */
 134         Form_pg_am      rd_am;                  /* pg_am tuple for index's AM */
 135
 136         /* index access support info (used only for an index relation) */
 137         MemoryContext rd_indexcxt;      /* private memory cxt for this stuff */
 138         IndexStrategy rd_istrat;        /* operator strategy map */
 139         Oid                *rd_operator;        /* OIDs of index operators */
 140         RegProcedure *rd_support;       /* OIDs of support procedures */
 141         struct FmgrInfo *rd_supportinfo;        /* lookup info for support
 142                                                                                  * procedures */
 143         /* "struct FmgrInfo" avoids need to include fmgr.h here */
 144
 145         /* statistics collection area */
 146         PgStat_Info pgstat_info;
 147 } RelationData;
 148
 149 typedef RelationData *Relation;
 150
 151
 152 /* ----------------
 153  *              RelationPtr is used in the executor to support index scans
 154  *              where we have to keep track of several index relations in an
 155  *              array.  -cim 9/10/89
 156  * ----------------
 157  */
 158 typedef Relation *RelationPtr;
 159
 160
 161 /*
 162  * RelationIsValid
 163  *              True iff relation descriptor is valid.
 164  */
 165 #define RelationIsValid(relation) PointerIsValid(relation)
 166
 167 #define InvalidRelation ((Relation) NULL)
 168
 169 /*
 170  * RelationHasReferenceCountZero
 171  *              True iff relation reference count is zero.
 172  *
 173  * Note:
 174  *              Assumes relation descriptor is valid.
 175  */
 176 #define RelationHasReferenceCountZero(relation) \
 177                 ((bool)((relation)->rd_refcnt == 0))
 178
 179 /*
 180  * RelationSetReferenceCount
 181  *              Sets relation reference count.
 182  */
 183 #define RelationSetReferenceCount(relation,count) \
 184         ((relation)->rd_refcnt = (count))
 185
 186 /*
 187  * RelationIncrementReferenceCount
 188  *              Increments relation reference count.
 189  */
 190 #define RelationIncrementReferenceCount(relation) \
 191         ((relation)->rd_refcnt += 1)
 192
 193 /*
 194  * RelationDecrementReferenceCount
 195  *              Decrements relation reference count.
 196  */
 197 #define RelationDecrementReferenceCount(relation) \
 198         (AssertMacro((relation)->rd_refcnt > 0), \
 199          (relation)->rd_refcnt -= 1)
 200
 201 /*
 202  * RelationGetForm
 203  *              Returns pg_class tuple for a relation.
 204  *
 205  * Note:
 206  *              Assumes relation descriptor is valid.
 207  */
 208 #define RelationGetForm(relation) ((relation)->rd_rel)
 209
 210 /*
 211  * RelationGetRelid
 212  *
 213  *      returns the OID of the relation
 214  */
 215 #define RelationGetRelid(relation) ((relation)->rd_id)
 216
 217 /*
 218  * RelationGetFile
 219  *
 220  *        Returns the open file descriptor for the rel
 221  */
 222 #define RelationGetFile(relation) ((relation)->rd_fd)
 223
 224 /*
 225  * RelationGetNumberOfAttributes
 226  *
 227  *        Returns the number of attributes.
 228  */
 229 #define RelationGetNumberOfAttributes(relation) ((relation)->rd_rel->relnatts)
 230
 231 /*
 232  * RelationGetDescr
 233  *              Returns tuple descriptor for a relation.
 234  */
 235 #define RelationGetDescr(relation) ((relation)->rd_att)
 236
 237 /*
 238  * RelationGetIndexStrategy
 239  *              Returns index strategy for a relation.
 240  *
 241  * Note:
 242  *              Assumes relation descriptor is valid.
 243  *              Assumes relation descriptor is for an index relation.
 244  */
 245 #define RelationGetIndexStrategy(relation) ((relation)->rd_istrat)
 246
 247 /*
 248  * RelationGetRelationName
 249  *
 250  *        Returns the rel's name.
 251  *
 252  * Note that the name is only unique within the containing namespace.
 253  */
 254 #define RelationGetRelationName(relation) \
 255         (NameStr((relation)->rd_rel->relname))
 256
 257 /*
 258  * RelationGetNamespace
 259  *
 260  *        Returns the rel's namespace OID.
 261  */
 262 #define RelationGetNamespace(relation) \
 263         ((relation)->rd_rel->relnamespace)
 264
 265 #endif   /* REL_H */