forked from pingcap/tidb
/
partition_prune.go
46 lines (43 loc) · 1.82 KB
/
partition_prune.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
// Copyright 2020 PingCAP, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package core
import (
"github.com/twotigers93/tidb/expression"
"github.com/twotigers93/tidb/parser/model"
"github.com/twotigers93/tidb/sessionctx"
"github.com/twotigers93/tidb/table"
"github.com/twotigers93/tidb/types"
)
// PartitionPruning finds all used partitions according to query conditions, it will
// return nil if condition match none of partitions. The return value is a array of the
// idx in the partition definitions array, use pi.Definitions[idx] to get the partition ID
func PartitionPruning(ctx sessionctx.Context, tbl table.PartitionedTable, conds []expression.Expression, partitionNames []model.CIStr,
columns []*expression.Column, names types.NameSlice) ([]int, error) {
s := partitionProcessor{}
pi := tbl.Meta().Partition
switch pi.Type {
case model.PartitionTypeHash, model.PartitionTypeKey:
return s.pruneHashOrKeyPartition(ctx, tbl, partitionNames, conds, columns, names)
case model.PartitionTypeRange:
rangeOr, err := s.pruneRangePartition(ctx, pi, tbl, conds, columns, names)
if err != nil {
return nil, err
}
ret := s.convertToIntSlice(rangeOr, pi, partitionNames)
return ret, nil
case model.PartitionTypeList:
return s.pruneListPartition(ctx, tbl, partitionNames, conds, columns)
}
return []int{FullRange}, nil
}