ClickHouse/src/Storages/TTLDescription.h
2020-08-08 03:47:03 +03:00

114 lines
3.4 KiB
C++

#pragma once
#include <Parsers/IAST_fwd.h>
#include <Storages/DataDestinationType.h>
#include <Storages/ColumnsDescription.h>
#include <Storages/KeyDescription.h>
#include <Interpreters/ExpressionActions.h>
#include <Interpreters/AggregateDescription.h>
#include <Storages/TTLMode.h>
namespace DB
{
/// Assignment expression in TTL with GROUP BY
struct TTLAggregateDescription
{
/// Name of column in assignment
/// x = sum(y)
/// ^
String column_name;
/// Name of column on the right hand of the assignment
/// x = sum(y)
/// ^~~~~~^
String expression_result_column_name;
/// Expressions to calculate the value of assignment expression
ExpressionActionsPtr expression;
TTLAggregateDescription() = default;
TTLAggregateDescription(const TTLAggregateDescription & other);
TTLAggregateDescription & operator=(const TTLAggregateDescription & other);
};
using TTLAggregateDescriptions = std::vector<TTLAggregateDescription>;
/// Common struct for TTL record in storage
struct TTLDescription
{
TTLMode mode;
/// Expression part of TTL AST:
/// TTL d + INTERVAL 1 DAY
/// ^~~~~~~~~~~~~~~~~~~^
ASTPtr expression_ast;
/// Expression actions evaluated from AST
ExpressionActionsPtr expression;
/// Result column of this TTL expression
String result_column;
/// WHERE part in TTL expression
/// TTL ... WHERE x % 10 == 0 and y > 5
/// ^~~~~~~~~~~~~~~~~~~~~~^
ExpressionActionsPtr where_expression;
/// Name of result column from WHERE expression
String where_result_column;
/// Names of key columns in GROUP BY expression
/// TTL ... GROUP BY toDate(d), x SET ...
/// ^~~~~~~~~~~~^
Names group_by_keys;
/// SET parts of TTL expression
TTLAggregateDescriptions set_parts;
/// Aggregate descriptions for GROUP BY in TTL
AggregateDescriptions aggregate_descriptions;
/// Destination type, only valid for table TTLs.
/// For example DISK or VOLUME
DataDestinationType destination_type;
/// Name of destination disk or volume
String destination_name;
/// Parse TTL structure from definition. Able to parse both column and table
/// TTLs.
static TTLDescription getTTLFromAST(const ASTPtr & definition_ast, const ColumnsDescription & columns, const Context & context, const KeyDescription & primary_key);
TTLDescription() = default;
TTLDescription(const TTLDescription & other);
TTLDescription & operator=(const TTLDescription & other);
};
/// Mapping from column name to column TTL
using TTLColumnsDescription = std::unordered_map<String, TTLDescription>;
using TTLDescriptions = std::vector<TTLDescription>;
/// Common TTL for all table. Specified after defining the table columns.
struct TTLTableDescription
{
/// Definition. Include all parts of TTL:
/// TTL d + INTERVAL 1 day TO VOLUME 'disk1'
/// ^~~~~~~~~~~~~~~definition~~~~~~~~~~~~~~~^
ASTPtr definition_ast;
/// Rows removing TTL
TTLDescription rows_ttl;
/// Moving data TTL (to other disks or volumes)
TTLDescriptions move_ttl;
TTLTableDescription() = default;
TTLTableDescription(const TTLTableDescription & other);
TTLTableDescription & operator=(const TTLTableDescription & other);
static TTLTableDescription getTTLForTableFromAST(
const ASTPtr & definition_ast, const ColumnsDescription & columns, const Context & context, const KeyDescription & primary_key);
};
}