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
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
|
/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.drill.exec.planner.logical;
import java.io.IOException;
import java.util.List;
import org.apache.drill.common.JSONOptions;
import org.apache.drill.common.exceptions.DrillRuntimeException;
import org.apache.drill.common.expression.SchemaPath;
import org.apache.drill.common.logical.data.LogicalOperator;
import org.apache.drill.common.logical.data.Scan;
import org.apache.drill.exec.physical.base.AbstractGroupScan;
import org.apache.drill.exec.physical.base.GroupScan;
import org.apache.drill.exec.physical.base.ScanStats;
import org.apache.drill.exec.planner.common.DrillScanRelBase;
import org.apache.drill.exec.planner.cost.DrillCostBase.DrillCostFactory;
import org.apache.drill.exec.planner.physical.PrelUtil;
import org.apache.drill.exec.planner.torel.ConversionContext;
import org.eigenbase.rel.RelWriter;
import org.eigenbase.relopt.RelOptCluster;
import org.eigenbase.relopt.RelOptCost;
import org.eigenbase.relopt.RelOptPlanner;
import org.eigenbase.relopt.RelOptTable;
import org.eigenbase.relopt.RelTraitSet;
import org.eigenbase.reltype.RelDataType;
import com.google.common.base.Preconditions;
import com.google.common.base.Predicate;
import com.google.common.collect.Iterables;
/**
* GroupScan of a Drill table.
*/
public class DrillScanRel extends DrillScanRelBase implements DrillRel {
private final static int STAR_COLUMN_COST = 10000;
final private RelDataType rowType;
private GroupScan groupScan;
/** Creates a DrillScan. */
public DrillScanRel(RelOptCluster cluster, RelTraitSet traits,
RelOptTable table) {
// By default, scan does not support project pushdown.
// Decision whether push projects into scan will be made solely in DrillPushProjIntoScanRule.
this(cluster, traits, table, table.getRowType(), AbstractGroupScan.ALL_COLUMNS);
}
/** Creates a DrillScan. */
public DrillScanRel(RelOptCluster cluster, RelTraitSet traits,
RelOptTable table, RelDataType rowType, List<SchemaPath> columns) {
super(DRILL_LOGICAL, cluster, traits, table);
this.rowType = rowType;
columns = columns == null || columns.size() == 0 ? GroupScan.ALL_COLUMNS : columns;
try {
this.groupScan = drillTable.getGroupScan().clone(columns);
} catch (IOException e) {
throw new DrillRuntimeException("Failure creating scan.", e);
}
}
//
// private static GroupScan getCopy(GroupScan scan){
// try {
// return (GroupScan) scan.getNewWithChildren((List<PhysicalOperator>) (Object) Collections.emptyList());
// } catch (ExecutionSetupException e) {
// throw new DrillRuntimeException("Unexpected failure while coping node.", e);
// }
// }
@Override
public LogicalOperator implement(DrillImplementor implementor) {
Scan.Builder builder = Scan.builder();
builder.storageEngine(drillTable.getStorageEngineName());
builder.selection(new JSONOptions(drillTable.getSelection()));
implementor.registerSource(drillTable);
return builder.build();
}
public static DrillScanRel convert(Scan scan, ConversionContext context) {
return new DrillScanRel(context.getCluster(), context.getLogicalTraits(),
context.getTable(scan));
}
@Override
public RelDataType deriveRowType() {
return this.rowType;
}
@Override
public RelWriter explainTerms(RelWriter pw) {
return super.explainTerms(pw).item("groupscan", groupScan.getDigest());
}
@Override
public double getRows() {
return this.groupScan.getScanStats().getRecordCount();
}
/// TODO: this method is same as the one for ScanPrel...eventually we should consolidate
/// this and few other methods in a common base class which would be extended
/// by both logical and physical rels.
@Override
public RelOptCost computeSelfCost(RelOptPlanner planner) {
ScanStats stats = groupScan.getScanStats();
int columnCount = getRowType().getFieldCount();
double ioCost = 0;
boolean isStarQuery = Iterables.tryFind(getRowType().getFieldNames(), new Predicate<String>() {
@Override
public boolean apply(String input) {
return Preconditions.checkNotNull(input).equals("*");
}
}).isPresent();
if (isStarQuery) {
columnCount = STAR_COLUMN_COST;
}
// double rowCount = RelMetadataQuery.getRowCount(this);
double rowCount = stats.getRecordCount();
if (rowCount < 1) {
rowCount = 1;
}
if(PrelUtil.getSettings(getCluster()).useDefaultCosting()) {
return planner.getCostFactory().makeCost(rowCount * columnCount, stats.getCpuCost(), stats.getDiskCost());
}
double cpuCost = rowCount * columnCount; // for now, assume cpu cost is proportional to row count.
// Even though scan is reading from disk, in the currently generated plans all plans will
// need to read the same amount of data, so keeping the disk io cost 0 is ok for now.
// In the future we might consider alternative scans that go against projections or
// different compression schemes etc that affect the amount of data read. Such alternatives
// would affect both cpu and io cost.
DrillCostFactory costFactory = (DrillCostFactory)planner.getCostFactory();
return costFactory.makeCost(rowCount, cpuCost, ioCost, 0);
}
public GroupScan getGroupScan() {
return groupScan;
}
}
|
