ClickHouse/dbms/src/Storages/MergeTree/ReplicatedMergeTreeLogEntry.h

108 lines
4.0 KiB
C++

#pragma once
#include <Common/Exception.h>
#include <Core/Types.h>
#include <IO/WriteHelpers.h>
#include <mutex>
#include <condition_variable>
struct Stat;
namespace DB
{
class ReadBuffer;
class WriteBuffer;
class ReplicatedMergeTreeQueue;
namespace ErrorCodes
{
extern const int LOGICAL_ERROR;
extern const int UNKNOWN_FORMAT_VERSION;
extern const int CANNOT_PARSE_TEXT;
}
/// Record about what needs to be done. Only data (you can copy them).
struct ReplicatedMergeTreeLogEntryData
{
enum Type
{
EMPTY, /// Not used.
GET_PART, /// Get the part from another replica.
MERGE_PARTS, /// Merge the parts.
DROP_RANGE, /// Delete the parts in the specified partition in the specified number range.
ATTACH_PART, /// Move a part from the `detached` directory. Obsolete. TODO: Remove after half year.
CLEAR_COLUMN, /// Drop specific column from specified partition.
};
String typeToString() const
{
switch (type)
{
case ReplicatedMergeTreeLogEntryData::GET_PART: return "GET_PART";
case ReplicatedMergeTreeLogEntryData::MERGE_PARTS: return "MERGE_PARTS";
case ReplicatedMergeTreeLogEntryData::DROP_RANGE: return "DROP_RANGE";
case ReplicatedMergeTreeLogEntryData::ATTACH_PART: return "ATTACH_PART";
case ReplicatedMergeTreeLogEntryData::CLEAR_COLUMN: return "CLEAR_COLUMN";
default:
throw Exception("Unknown log entry type: " + DB::toString<int>(type), ErrorCodes::LOGICAL_ERROR);
}
}
void writeText(WriteBuffer & out) const;
void readText(ReadBuffer & in);
String toString() const;
String znode_name;
Type type = EMPTY;
String source_replica; /// Empty string means that this entry was added to the queue immediately, and not copied from the log.
/// The name of resulting part.
/// For DROP_RANGE, the name of a non-existent part. You need to remove all the parts covered by it.
String new_part_name;
String block_id; /// For parts of level zero, the block identifier for deduplication (node name in /blocks/).
mutable String actual_new_part_name; /// GET_PART could actually fetch a part covering 'new_part_name'.
Strings parts_to_merge;
bool deduplicate = false; /// Do deduplicate on merge
String column_name;
/// For DROP_RANGE, true means that the parts need not be deleted, but moved to the `detached` directory.
bool detach = false;
/// Access under queue_mutex, see ReplicatedMergeTreeQueue.
bool currently_executing = false; /// Whether the action is executing now.
/// These several fields are informational only (for viewing by the user using system tables).
/// Access under queue_mutex, see ReplicatedMergeTreeQueue.
size_t num_tries = 0; /// The number of attempts to perform the action (since the server started, including the running one).
std::exception_ptr exception; /// The last exception, in the case of an unsuccessful attempt to perform the action.
time_t last_attempt_time = 0; /// The time at which the last attempt was attempted to complete the action.
size_t num_postponed = 0; /// The number of times the action was postponed.
String postpone_reason; /// The reason why the action was postponed, if it was postponed.
time_t last_postpone_time = 0; /// The time of the last time the action was postponed.
/// Creation time or the time to copy from the general log to the queue of a particular replica.
time_t create_time = 0;
/// The quorum value (for GET_PART) is a non-zero value when the quorum write is enabled.
size_t quorum = 0;
};
struct ReplicatedMergeTreeLogEntry : ReplicatedMergeTreeLogEntryData
{
using Ptr = std::shared_ptr<ReplicatedMergeTreeLogEntry>;
std::condition_variable execution_complete; /// Awake when currently_executing becomes false.
static Ptr parse(const String & s, const Stat & stat);
};
}