src/include/access/strat.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * strat.h--
   4  *    index strategy type definitions
   5  *    (separated out from original istrat.h to avoid circular refs)
   6  *
   7  *
   8  * Copyright (c) 1994, Regents of the University of California
   9  *
  10  * $Id: strat.h,v 1.2 1996/10/19 04:05:44 scrappy Exp $
  11  *
  12  *-------------------------------------------------------------------------
  13  */
  14 #ifndef STRAT_H
  15 #define STRAT_H
  16
  17 #include "access/skey.h"
  18
  19 typedef uint16  StrategyNumber;
  20
  21 #define InvalidStrategy 0
  22
  23 typedef struct StrategyTransformMapData {
  24     StrategyNumber      strategy[1];    /* VARIABLE LENGTH ARRAY */
  25 } StrategyTransformMapData;     /* VARIABLE LENGTH STRUCTURE */
  26
  27 typedef StrategyTransformMapData        *StrategyTransformMap;
  28
  29 typedef struct StrategyOperatorData {
  30     StrategyNumber      strategy;
  31     bits16              flags;          /* scan qualification flags h/skey.h */
  32 } StrategyOperatorData;
  33
  34 typedef StrategyOperatorData    *StrategyOperator;
  35
  36 typedef struct StrategyTermData {       /* conjunctive term */
  37     uint16                      degree;
  38     StrategyOperatorData        operatorData[1];        /* VARIABLE LENGTH */
  39 } StrategyTermData;     /* VARIABLE LENGTH STRUCTURE */
  40
  41 typedef StrategyTermData        *StrategyTerm;
  42
  43 typedef struct StrategyExpressionData { /* disjunctive normal form */
  44     StrategyTerm        term[1];        /* VARIABLE LENGTH ARRAY */
  45 } StrategyExpressionData;       /* VARIABLE LENGTH STRUCTURE */
  46
  47 typedef StrategyExpressionData  *StrategyExpression;
  48
  49 typedef struct StrategyEvaluationData {
  50     StrategyNumber              maxStrategy;
  51     StrategyTransformMap        negateTransform;
  52     StrategyTransformMap        commuteTransform;
  53     StrategyTransformMap        negateCommuteTransform;
  54     StrategyExpression  expression[12]; /* XXX VARIABLE LENGTH */
  55 } StrategyEvaluationData;       /* VARIABLE LENGTH STRUCTURE */
  56
  57 typedef StrategyEvaluationData  *StrategyEvaluation;
  58
  59 /*
  60  * StrategyTransformMapIsValid --
  61  *      Returns true iff strategy transformation map is valid.
  62  */
  63 #define StrategyTransformMapIsValid(transform) PointerIsValid(transform)
  64
  65
  66 #ifndef CorrectStrategies               /* XXX this should be removable */
  67 #define AMStrategies(foo)       12
  68 #else   /* !defined(CorrectStrategies) */
  69 #define AMStrategies(foo)       (foo)
  70 #endif  /* !defined(CorrectStrategies) */
  71
  72 typedef struct StrategyMapData {
  73         ScanKeyData             entry[1];       /* VARIABLE LENGTH ARRAY */
  74 } StrategyMapData;      /* VARIABLE LENGTH STRUCTURE */
  75
  76 typedef StrategyMapData *StrategyMap;
  77
  78 typedef struct IndexStrategyData {
  79         StrategyMapData strategyMapData[1];     /* VARIABLE LENGTH ARRAY */
  80 } IndexStrategyData;    /* VARIABLE LENGTH STRUCTURE */
  81
  82 typedef IndexStrategyData       *IndexStrategy;
  83
  84 #endif /*STRAT_H */