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partbounds.h
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1 /*-------------------------------------------------------------------------
2  *
3  * partbounds.h
4  *
5  * Copyright (c) 2007-2021, PostgreSQL Global Development Group
6  *
7  * src/include/partitioning/partbounds.h
8  *
9  *-------------------------------------------------------------------------
10  */
11 #ifndef PARTBOUNDS_H
12 #define PARTBOUNDS_H
13 
14 #include "fmgr.h"
15 #include "parser/parse_node.h"
16 #include "partitioning/partdefs.h"
17 
18 struct RelOptInfo; /* avoid including pathnodes.h here */
19 
20 
21 /*
22  * PartitionBoundInfoData encapsulates a set of partition bounds. It is
23  * usually associated with partitioned tables as part of its partition
24  * descriptor, but may also be used to represent a virtual partitioned
25  * table such as a partitioned joinrel within the planner.
26  *
27  * A list partition datum that is known to be NULL is never put into the
28  * datums array. Instead, it is tracked using the null_index field.
29  *
30  * In the case of range partitioning, ndatums will typically be far less than
31  * 2 * nparts, because a partition's upper bound and the next partition's lower
32  * bound are the same in most common cases, and we only store one of them (the
33  * upper bound). In case of hash partitioning, ndatums will be the same as the
34  * number of partitions.
35  *
36  * For range and list partitioned tables, datums is an array of datum-tuples
37  * with key->partnatts datums each. For hash partitioned tables, it is an array
38  * of datum-tuples with 2 datums, modulus and remainder, corresponding to a
39  * given partition.
40  *
41  * The datums in datums array are arranged in increasing order as defined by
42  * functions qsort_partition_rbound_cmp(), qsort_partition_list_value_cmp() and
43  * qsort_partition_hbound_cmp() for range, list and hash partitioned tables
44  * respectively. For range and list partitions this simply means that the
45  * datums in the datums array are arranged in increasing order as defined by
46  * the partition key's operator classes and collations.
47  *
48  * In the case of list partitioning, the indexes array stores one entry for
49  * each datum-array entry, which is the index of the partition that accepts
50  * rows matching that datum. So nindexes == ndatums.
51  *
52  * In the case of range partitioning, the indexes array stores one entry per
53  * distinct range datum, which is the index of the partition for which that
54  * datum is an upper bound (or -1 for a "gap" that has no partition). It is
55  * convenient to have an extra -1 entry representing values above the last
56  * range datum, so nindexes == ndatums + 1.
57  *
58  * In the case of hash partitioning, the number of entries in the indexes
59  * array is the same as the greatest modulus amongst all partitions (which
60  * is a multiple of all partition moduli), so nindexes == greatest modulus.
61  * The indexes array is indexed according to the hash key's remainder modulo
62  * the greatest modulus, and it contains either the partition index accepting
63  * that remainder, or -1 if there is no partition for that remainder.
64  */
65 typedef struct PartitionBoundInfoData
66 {
67  char strategy; /* hash, list or range? */
68  int ndatums; /* Length of the datums[] array */
70  PartitionRangeDatumKind **kind; /* The kind of each range bound datum;
71  * NULL for hash and list partitioned
72  * tables */
73  int nindexes; /* Length of the indexes[] array */
74  int *indexes; /* Partition indexes */
75  int null_index; /* Index of the null-accepting partition; -1
76  * if there isn't one */
77  int default_index; /* Index of the default partition; -1 if there
78  * isn't one */
80 
81 #define partition_bound_accepts_nulls(bi) ((bi)->null_index != -1)
82 #define partition_bound_has_default(bi) ((bi)->default_index != -1)
83 
85 extern uint64 compute_partition_hash_value(int partnatts, FmgrInfo *partsupfunc,
86  Oid *partcollation,
87  Datum *values, bool *isnull);
88 extern List *get_qual_from_partbound(Relation rel, Relation parent,
89  PartitionBoundSpec *spec);
91  int nparts, PartitionKey key, int **mapping);
92 extern bool partition_bounds_equal(int partnatts, int16 *parttyplen,
93  bool *parttypbyval, PartitionBoundInfo b1,
97 extern PartitionBoundInfo partition_bounds_merge(int partnatts,
98  FmgrInfo *partsupfunc,
99  Oid *partcollation,
100  struct RelOptInfo *outer_rel,
101  struct RelOptInfo *inner_rel,
102  JoinType jointype,
103  List **outer_parts,
104  List **inner_parts);
105 extern bool partitions_are_ordered(PartitionBoundInfo boundinfo, int nparts);
106 extern void check_new_partition_bound(char *relname, Relation parent,
107  PartitionBoundSpec *spec,
108  ParseState *pstate);
109 extern void check_default_partition_contents(Relation parent,
110  Relation defaultRel,
111  PartitionBoundSpec *new_spec);
112 
113 extern int32 partition_rbound_datum_cmp(FmgrInfo *partsupfunc,
114  Oid *partcollation,
115  Datum *rb_datums, PartitionRangeDatumKind *rb_kind,
116  Datum *tuple_datums, int n_tuple_datums);
117 extern int partition_list_bsearch(FmgrInfo *partsupfunc,
118  Oid *partcollation,
119  PartitionBoundInfo boundinfo,
120  Datum value, bool *is_equal);
121 extern int partition_range_datum_bsearch(FmgrInfo *partsupfunc,
122  Oid *partcollation,
123  PartitionBoundInfo boundinfo,
124  int nvalues, Datum *values, bool *is_equal);
125 extern int partition_hash_bsearch(PartitionBoundInfo boundinfo,
126  int modulus, int remainder);
127 
128 #endif /* PARTBOUNDS_H */
signed short int16
Definition: c.h:428
Definition: fmgr.h:56
PartitionRangeDatumKind ** kind
Definition: partbounds.h:70
int partition_list_bsearch(FmgrInfo *partsupfunc, Oid *partcollation, PartitionBoundInfo boundinfo, Datum value, bool *is_equal)
Definition: partbounds.c:3499
bool partitions_are_ordered(PartitionBoundInfo boundinfo, int nparts)
Definition: partbounds.c:2738
PartitionRangeDatumKind
Definition: parsenodes.h:837
PartitionBoundInfo partition_bounds_create(PartitionBoundSpec **boundspecs, int nparts, PartitionKey key, int **mapping)
Definition: partbounds.c:304
NameData relname
Definition: pg_class.h:38
unsigned int Oid
Definition: postgres_ext.h:31
int partition_hash_bsearch(PartitionBoundInfo boundinfo, int modulus, int remainder)
Definition: partbounds.c:3630
signed int int32
Definition: c.h:429
JoinType
Definition: nodes.h:700
static struct @141 value
void check_default_partition_contents(Relation parent, Relation defaultRel, PartitionBoundSpec *new_spec)
Definition: partbounds.c:3143
bool partition_bounds_equal(int partnatts, int16 *parttyplen, bool *parttypbyval, PartitionBoundInfo b1, PartitionBoundInfo b2)
Definition: partbounds.c:801
struct PartitionBoundInfoData PartitionBoundInfoData
uintptr_t Datum
Definition: postgres.h:367
int32 partition_rbound_datum_cmp(FmgrInfo *partsupfunc, Oid *partcollation, Datum *rb_datums, PartitionRangeDatumKind *rb_kind, Datum *tuple_datums, int n_tuple_datums)
Definition: partbounds.c:3448
int get_hash_partition_greatest_modulus(PartitionBoundInfo b)
Definition: partbounds.c:3306
List * get_qual_from_partbound(Relation rel, Relation parent, PartitionBoundSpec *spec)
Definition: partbounds.c:249
void check_new_partition_bound(char *relname, Relation parent, PartitionBoundSpec *spec, ParseState *pstate)
Definition: partbounds.c:2797
static Datum values[MAXATTR]
Definition: bootstrap.c:165
PartitionBoundInfo partition_bounds_copy(PartitionBoundInfo src, PartitionKey key)
Definition: partbounds.c:907
uint64 compute_partition_hash_value(int partnatts, FmgrInfo *partsupfunc, Oid *partcollation, Datum *values, bool *isnull)
Definition: partbounds.c:4617
Definition: pg_list.h:50
int partition_range_datum_bsearch(FmgrInfo *partsupfunc, Oid *partcollation, PartitionBoundInfo boundinfo, int nvalues, Datum *values, bool *is_equal)
Definition: partbounds.c:3587
PartitionBoundInfo partition_bounds_merge(int partnatts, FmgrInfo *partsupfunc, Oid *partcollation, struct RelOptInfo *outer_rel, struct RelOptInfo *inner_rel, JoinType jointype, List **outer_parts, List **inner_parts)
Definition: partbounds.c:1006