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
|
#pragma once
#include <Functions/FunctionFactory.h>
#include <IO/WriteHelpers.h>
#include <Interpreters/InDepthNodeVisitor.h>
#include <Parsers/ASTFunction.h>
#include <Parsers/ASTSetQuery.h>
#include <Parsers/ASTTablesInSelectQuery.h>
#include <Parsers/IAST.h>
#include <Common/typeid_cast.h>
#include <Parsers/ASTSubquery.h>
namespace DB
{
/// Recursive traversal and check for optimizeAggregateFunctionsOfGroupByKeys
struct KeepAggregateFunctionMatcher
{
struct Data
{
const NameSet & group_by_keys;
bool keep_aggregator;
};
using Visitor = InDepthNodeVisitor<KeepAggregateFunctionMatcher, true>;
static bool needChildVisit(const ASTPtr & node, const ASTPtr &)
{
return !(node->as<ASTFunction>());
}
static void visit(ASTFunction & function_node, Data & data)
{
if (function_node.arguments->children.empty())
{
data.keep_aggregator = true;
return;
}
if (!data.group_by_keys.count(function_node.getColumnName()))
{
Visitor(data).visit(function_node.arguments);
}
}
static void visit(ASTIdentifier & ident, Data & data)
{
/// if variable of a function is not in GROUP BY keys, this function should not be deleted
if (!data.group_by_keys.count(ident.getColumnName()))
data.keep_aggregator = true;
}
static void visit(const ASTPtr & ast, Data & data)
{
if (data.keep_aggregator)
return;
if (auto * function_node = ast->as<ASTFunction>())
{
visit(*function_node, data);
}
else if (auto * ident = ast->as<ASTIdentifier>())
{
visit(*ident, data);
}
else if (!ast->as<ASTExpressionList>())
{
data.keep_aggregator = true;
}
}
};
using KeepAggregateFunctionVisitor = KeepAggregateFunctionMatcher::Visitor;
class SelectAggregateFunctionOfGroupByKeysMatcher
{
public:
struct Data
{
const NameSet & group_by_keys;
};
static bool needChildVisit(const ASTPtr & node, const ASTPtr &)
{
/// Don't descent into table functions and subqueries and special case for ArrayJoin.
return !node->as<ASTSubquery>() && !node->as<ASTTableExpression>()
&& !node->as<ASTSelectWithUnionQuery>() && !node->as<ASTArrayJoin>();
}
static void visit(ASTPtr & ast, Data & data)
{
/// Check if function is min/max/any
auto * function_node = ast->as<ASTFunction>();
if (function_node && (function_node->name == "min" || function_node->name == "max" ||
function_node->name == "any" || function_node->name == "anyLast"))
{
KeepAggregateFunctionVisitor::Data keep_data{data.group_by_keys, false};
if (function_node->arguments) KeepAggregateFunctionVisitor(keep_data).visit(function_node->arguments);
/// Place argument of an aggregate function instead of function
if (!keep_data.keep_aggregator && function_node->arguments && !function_node->arguments->children.empty())
{
String alias = function_node->alias;
ast = (function_node->arguments->children[0])->clone();
ast->setAlias(alias);
}
}
}
};
using SelectAggregateFunctionOfGroupByKeysVisitor = InDepthNodeVisitor<SelectAggregateFunctionOfGroupByKeysMatcher, true>;
}
|
