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 1.11 1998/09/01 04:34:30 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                                                                  * STRUCTURE */
  35
  36 typedef StrategyTransformMapData *StrategyTransformMap;
  37
  38 typedef struct StrategyOperatorData
  39 {
  40         StrategyNumber strategy;
  41         bits16          flags;                  /* scan qualification flags h/skey.h */
  42 } StrategyOperatorData;
  43
  44 typedef StrategyOperatorData *StrategyOperator;
  45
  46 typedef struct StrategyTermData
  47 {                                                               /* conjunctive term */
  48         uint16          degree;
  49         StrategyOperatorData operatorData[1];           /* VARIABLE LENGTH */
  50 } StrategyTermData;                             /* VARIABLE LENGTH STRUCTURE */
  51
  52 typedef StrategyTermData *StrategyTerm;
  53
  54 typedef struct StrategyExpressionData
  55 {                                                               /* disjunctive normal form */
  56         StrategyTerm term[1];           /* VARIABLE LENGTH ARRAY */
  57 } StrategyExpressionData;               /* VARIABLE LENGTH STRUCTURE */
  58
  59 typedef StrategyExpressionData *StrategyExpression;
  60
  61 typedef struct StrategyEvaluationData
  62 {
  63         StrategyNumber maxStrategy;
  64         StrategyTransformMap negateTransform;
  65         StrategyTransformMap commuteTransform;
  66         StrategyTransformMap negateCommuteTransform;
  67         StrategyExpression expression[12];      /* XXX VARIABLE LENGTH */
  68 } StrategyEvaluationData;               /* VARIABLE LENGTH STRUCTURE */
  69
  70 typedef StrategyEvaluationData *StrategyEvaluation;
  71
  72 /*
  73  * StrategyTransformMapIsValid --
  74  *              Returns true iff strategy transformation map is valid.
  75  */
  76 #define StrategyTransformMapIsValid(transform) PointerIsValid(transform)
  77
  78
  79 #define AMStrategies(foo)               (foo)
  80
  81 typedef struct StrategyMapData
  82 {
  83         ScanKeyData entry[1];           /* VARIABLE LENGTH ARRAY */
  84 } StrategyMapData;                              /* VARIABLE LENGTH STRUCTURE */
  85
  86 typedef StrategyMapData *StrategyMap;
  87
  88 typedef struct IndexStrategyData
  89 {
  90         StrategyMapData strategyMapData[1]; /* VARIABLE LENGTH ARRAY */
  91 } IndexStrategyData;                    /* VARIABLE LENGTH STRUCTURE */
  92
  93 typedef IndexStrategyData *IndexStrategy;
  94
  95 #endif   /* STRAT_H */