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 1.14 1999/05/25 22:04:56 momjian 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 {
  25         StrategyNumber strategy[1]; /* VARIABLE LENGTH ARRAY */
  26 } StrategyTransformMapData;             /* VARIABLE LENGTH
  27
  28                                                                  *
  29                                                                  *
  30                                                                  *
  31                                                                  *
  32                                                                  *
  33                                                                  *
  34                                                                  *
  35                                                                  *
  36                                                                  * STRUCTURE */
  37
  38 typedef StrategyTransformMapData *StrategyTransformMap;
  39
  40 typedef struct StrategyOperatorData
  41 {
  42         StrategyNumber strategy;
  43         bits16          flags;                  /* scan qualification flags h/skey.h */
  44 } StrategyOperatorData;
  45
  46 typedef StrategyOperatorData *StrategyOperator;
  47
  48 typedef struct StrategyTermData
  49 {                                                               /* conjunctive term */
  50         uint16          degree;
  51         StrategyOperatorData operatorData[1];           /* VARIABLE LENGTH */
  52 } StrategyTermData;                             /* VARIABLE LENGTH STRUCTURE */
  53
  54 typedef StrategyTermData *StrategyTerm;
  55
  56 typedef struct StrategyExpressionData
  57 {                                                               /* disjunctive normal form */
  58         StrategyTerm term[1];           /* VARIABLE LENGTH ARRAY */
  59 } StrategyExpressionData;               /* VARIABLE LENGTH STRUCTURE */
  60
  61 typedef StrategyExpressionData *StrategyExpression;
  62
  63 typedef struct StrategyEvaluationData
  64 {
  65         StrategyNumber maxStrategy;
  66         StrategyTransformMap negateTransform;
  67         StrategyTransformMap commuteTransform;
  68         StrategyTransformMap negateCommuteTransform;
  69         StrategyExpression expression[12];      /* XXX VARIABLE LENGTH */
  70 } StrategyEvaluationData;               /* VARIABLE LENGTH STRUCTURE */
  71
  72 typedef StrategyEvaluationData *StrategyEvaluation;
  73
  74 /*
  75  * StrategyTransformMapIsValid
  76  *              Returns true iff strategy transformation map is valid.
  77  */
  78 #define StrategyTransformMapIsValid(transform) PointerIsValid(transform)
  79
  80
  81 #define AMStrategies(foo)               (foo)
  82
  83 typedef struct StrategyMapData
  84 {
  85         ScanKeyData entry[1];           /* VARIABLE LENGTH ARRAY */
  86 } StrategyMapData;                              /* VARIABLE LENGTH STRUCTURE */
  87
  88 typedef StrategyMapData *StrategyMap;
  89
  90 typedef struct IndexStrategyData
  91 {
  92         StrategyMapData strategyMapData[1]; /* VARIABLE LENGTH ARRAY */
  93 } IndexStrategyData;                    /* VARIABLE LENGTH STRUCTURE */
  94
  95 typedef IndexStrategyData *IndexStrategy;
  96
  97 #endif   /* STRAT_H */