ClickHouse/src/Storages/MergeTree/MergeTreePartition.cpp
Nikolai Kochetov 4aa6e4d683 Revert "Add return flag for preFinalize."
This reverts commit 3261378ef8.
2023-02-09 19:51:09 +00:00

496 lines
17 KiB
C++

#include <Storages/MergeTree/MergeTreePartition.h>
#include <Storages/MergeTree/MergeTreeData.h>
#include <Storages/MergeTree/IMergeTreeDataPart.h>
#include <IO/HashingWriteBuffer.h>
#include <Interpreters/Context.h>
#include <Common/FieldVisitors.h>
#include <DataTypes/DataTypeDate.h>
#include <DataTypes/DataTypeIPv4andIPv6.h>
#include <DataTypes/DataTypeTuple.h>
#include <Columns/ColumnTuple.h>
#include <Common/SipHash.h>
#include <Common/FieldVisitorToString.h>
#include <Common/FieldVisitorHash.h>
#include <Common/typeid_cast.h>
#include <Common/hex.h>
#include <Core/Block.h>
namespace DB
{
namespace ErrorCodes
{
extern const int LOGICAL_ERROR;
extern const int INVALID_PARTITION_VALUE;
}
namespace
{
/// This is a special visitor which is used to get partition ID.
/// Calculate hash for UUID the same way as for UInt128.
/// It worked this way until 21.5, and we cannot change it,
/// or partition ID will be different in case UUID is used in partition key.
/// (It is not recommended to use UUID as partition key).
/// NOTE: The code is intentionally copy-pasted,
/// so when FieldVisitorHash is changed, LegacyFieldVisitorHash will not change.
class LegacyFieldVisitorHash : public StaticVisitor<>
{
private:
SipHash & hash;
public:
explicit LegacyFieldVisitorHash(SipHash & hash_) : hash(hash_) {}
void operator() (const Null &) const
{
UInt8 type = Field::Types::Null;
hash.update(type);
}
void operator() (const UInt64 & x) const
{
UInt8 type = Field::Types::UInt64;
hash.update(type);
hash.update(x);
}
void operator() (const UInt128 & x) const
{
UInt8 type = Field::Types::UInt128;
hash.update(type);
hash.update(x);
}
void operator() (const UInt256 & x) const
{
UInt8 type = Field::Types::UInt256;
hash.update(type);
hash.update(x);
}
void operator() (const Int64 & x) const
{
UInt8 type = Field::Types::Int64;
hash.update(type);
hash.update(x);
}
void operator() (const Int128 & x) const
{
UInt8 type = Field::Types::Int128;
hash.update(type);
hash.update(x);
}
void operator() (const Int256 & x) const
{
UInt8 type = Field::Types::Int256;
hash.update(type);
hash.update(x);
}
void operator() (const UUID & x) const
{
operator()(x.toUnderType());
}
void operator() (const IPv4 & x) const
{
UInt8 type = Field::Types::IPv4;
hash.update(type);
hash.update(x);
}
void operator() (const IPv6 & x) const
{
return operator()(String(reinterpret_cast<const char *>(&x), 16));
}
void operator() (const Float64 & x) const
{
UInt8 type = Field::Types::Float64;
hash.update(type);
hash.update(x);
}
void operator() (const String & x) const
{
UInt8 type = Field::Types::String;
hash.update(type);
hash.update(x.size());
hash.update(x.data(), x.size());
}
void operator() (const Array & x) const
{
UInt8 type = Field::Types::Array;
hash.update(type);
hash.update(x.size());
for (const auto & elem : x)
applyVisitor(*this, elem);
}
void operator() (const Tuple & x) const
{
UInt8 type = Field::Types::Tuple;
hash.update(type);
hash.update(x.size());
for (const auto & elem : x)
applyVisitor(*this, elem);
}
void operator() (const Map & x) const
{
UInt8 type = Field::Types::Map;
hash.update(type);
hash.update(x.size());
for (const auto & elem : x)
applyVisitor(*this, elem);
}
void operator() (const Object & x) const
{
UInt8 type = Field::Types::Object;
hash.update(type);
hash.update(x.size());
for (const auto & [key, value]: x)
{
hash.update(key);
applyVisitor(*this, value);
}
}
void operator() (const DecimalField<Decimal32> & x) const
{
UInt8 type = Field::Types::Decimal32;
hash.update(type);
hash.update(x.getValue().value);
}
void operator() (const DecimalField<Decimal64> & x) const
{
UInt8 type = Field::Types::Decimal64;
hash.update(type);
hash.update(x.getValue().value);
}
void operator() (const DecimalField<Decimal128> & x) const
{
UInt8 type = Field::Types::Decimal128;
hash.update(type);
hash.update(x.getValue().value);
}
void operator() (const DecimalField<Decimal256> & x) const
{
UInt8 type = Field::Types::Decimal256;
hash.update(type);
hash.update(x.getValue().value);
}
void operator() (const AggregateFunctionStateData & x) const
{
UInt8 type = Field::Types::AggregateFunctionState;
hash.update(type);
hash.update(x.name.size());
hash.update(x.name.data(), x.name.size());
hash.update(x.data.size());
hash.update(x.data.data(), x.data.size());
}
void operator() (const CustomType & x) const
{
UInt8 type = Field::Types::CustomType;
hash.update(type);
hash.update(x.getTypeName());
auto result = x.toString();
hash.update(result.size());
hash.update(result.data(), result.size());
}
void operator() (const bool & x) const
{
UInt8 type = Field::Types::Bool;
hash.update(type);
hash.update(x);
}
};
}
String MergeTreePartition::getID(const MergeTreeData & storage) const
{
return getID(storage.getInMemoryMetadataPtr()->getPartitionKey().sample_block);
}
/// NOTE: This ID is used to create part names which are then persisted in ZK and as directory names on the file system.
/// So if you want to change this method, be sure to guarantee compatibility with existing table data.
String MergeTreePartition::getID(const Block & partition_key_sample) const
{
if (value.size() != partition_key_sample.columns())
throw Exception(ErrorCodes::LOGICAL_ERROR, "Invalid partition key size: {}", value.size());
if (value.empty())
return "all"; /// It is tempting to use an empty string here. But that would break directory structure in ZK.
/// In case all partition fields are represented by integral types, try to produce a human-readable ID.
/// Otherwise use a hex-encoded hash.
/// NOTE It will work in unexpected way if some partition key column is Nullable:
/// are_all_integral will be false if some value is NULL. Maybe we should fix it.
bool are_all_integral = true;
for (const Field & field : value)
{
if (field.getType() != Field::Types::UInt64 && field.getType() != Field::Types::Int64 && field.getType() != Field::Types::IPv4)
{
are_all_integral = false;
break;
}
}
String result;
if (are_all_integral)
{
FieldVisitorToString to_string_visitor;
for (size_t i = 0; i < value.size(); ++i)
{
if (i > 0)
result += '-';
if (typeid_cast<const DataTypeDate *>(partition_key_sample.getByPosition(i).type.get()))
result += toString(DateLUT::instance().toNumYYYYMMDD(DayNum(value[i].safeGet<UInt64>())));
else if (typeid_cast<const DataTypeIPv4 *>(partition_key_sample.getByPosition(i).type.get()))
result += toString(value[i].get<IPv4>().toUnderType());
else
result += applyVisitor(to_string_visitor, value[i]);
/// It is tempting to output DateTime as YYYYMMDDhhmmss, but that would make partition ID
/// timezone-dependent.
}
return result;
}
SipHash hash;
LegacyFieldVisitorHash hashing_visitor(hash);
for (const Field & field : value)
applyVisitor(hashing_visitor, field);
char hash_data[16];
hash.get128(hash_data);
result.resize(32);
for (size_t i = 0; i < 16; ++i)
writeHexByteLowercase(hash_data[i], &result[2 * i]);
return result;
}
std::optional<Row> MergeTreePartition::tryParseValueFromID(const String & partition_id, const Block & partition_key_sample)
{
size_t num_keys = partition_key_sample.columns();
Row res;
res.reserve(num_keys);
ReadBufferFromString buf(partition_id);
if (num_keys == 0)
{
checkString("all", buf);
assertEOF(buf);
return res;
}
enum KeyType { DATE, UNSIGNED, SIGNED };
std::vector<KeyType> key_types;
key_types.reserve(num_keys);
for (size_t i = 0; i < num_keys; ++i)
{
auto type = partition_key_sample.getByPosition(i).type;
/// NOTE Sometimes it's possible to parse Nullable key, but easier to ignore it.
if (type->isNullable())
return {};
/// We use Field::Types when serializing partition_id, let's get some Field to check type
Field sample_field = type->getDefault();
if (typeid_cast<const DataTypeDate *>(type.get()))
key_types.emplace_back(DATE);
else if (sample_field.getType() == Field::Types::UInt64)
key_types.emplace_back(UNSIGNED);
else if (sample_field.getType() == Field::Types::Int64)
key_types.emplace_back(SIGNED);
else
return {};
}
/// All columns are numeric, will parse partition value
for (size_t i = 0; i < num_keys; ++i)
{
switch (key_types[i])
{
case DATE:
{
UInt32 date_yyyymmdd;
readText(date_yyyymmdd, buf);
constexpr UInt32 min_yyyymmdd = 10000000;
constexpr UInt32 max_yyyymmdd = 99999999;
if (date_yyyymmdd < min_yyyymmdd || max_yyyymmdd < date_yyyymmdd)
throw Exception(
ErrorCodes::INVALID_PARTITION_VALUE, "Cannot parse partition_id: got unexpected Date: {}", date_yyyymmdd);
UInt32 date = DateLUT::instance().YYYYMMDDToDayNum(date_yyyymmdd);
res.emplace_back(date);
break;
}
case UNSIGNED:
{
UInt64 value;
readText(value, buf);
res.emplace_back(value);
break;
}
case SIGNED:
{
Int64 value;
readText(value, buf);
res.emplace_back(value);
break;
}
}
if (i + 1 != num_keys)
assertChar('-', buf);
}
assertEOF(buf);
String expected_partition_id = MergeTreePartition{res}.getID(partition_key_sample);
if (expected_partition_id != partition_id)
throw Exception(ErrorCodes::LOGICAL_ERROR, "Partition ID was parsed incorrectly: expected {}, got {}",
expected_partition_id, partition_id);
return res;
}
void MergeTreePartition::serializeText(const MergeTreeData & storage, WriteBuffer & out, const FormatSettings & format_settings) const
{
auto metadata_snapshot = storage.getInMemoryMetadataPtr();
const auto & partition_key_sample = metadata_snapshot->getPartitionKey().sample_block;
size_t key_size = partition_key_sample.columns();
if (key_size == 0)
{
writeCString("tuple()", out);
}
else if (key_size == 1)
{
const DataTypePtr & type = partition_key_sample.getByPosition(0).type;
auto column = type->createColumn();
column->insert(value[0]);
type->getDefaultSerialization()->serializeText(*column, 0, out, format_settings);
}
else
{
DataTypes types;
Columns columns;
for (size_t i = 0; i < key_size; ++i)
{
const auto & type = partition_key_sample.getByPosition(i).type;
types.push_back(type);
auto column = type->createColumn();
column->insert(value[i]);
columns.push_back(std::move(column));
}
auto tuple_serialization = DataTypeTuple(types).getDefaultSerialization();
auto tuple_column = ColumnTuple::create(columns);
tuple_serialization->serializeText(*tuple_column, 0, out, format_settings);
}
}
void MergeTreePartition::load(const MergeTreeData & storage, const PartMetadataManagerPtr & manager)
{
auto metadata_snapshot = storage.getInMemoryMetadataPtr();
if (!metadata_snapshot->hasPartitionKey())
return;
const auto & partition_key_sample = adjustPartitionKey(metadata_snapshot, storage.getContext()).sample_block;
auto file = manager->read("partition.dat");
value.resize(partition_key_sample.columns());
for (size_t i = 0; i < partition_key_sample.columns(); ++i)
partition_key_sample.getByPosition(i).type->getDefaultSerialization()->deserializeBinary(value[i], *file, {});
}
std::unique_ptr<WriteBufferFromFileBase> MergeTreePartition::store(const MergeTreeData & storage, IDataPartStorage & data_part_storage, MergeTreeDataPartChecksums & checksums) const
{
auto metadata_snapshot = storage.getInMemoryMetadataPtr();
const auto & context = storage.getContext();
const auto & partition_key_sample = adjustPartitionKey(metadata_snapshot, storage.getContext()).sample_block;
return store(partition_key_sample, data_part_storage, checksums, context->getWriteSettings());
}
std::unique_ptr<WriteBufferFromFileBase> MergeTreePartition::store(const Block & partition_key_sample, IDataPartStorage & data_part_storage, MergeTreeDataPartChecksums & checksums, const WriteSettings & settings) const
{
if (!partition_key_sample)
return nullptr;
auto out = data_part_storage.writeFile("partition.dat", DBMS_DEFAULT_BUFFER_SIZE, settings);
HashingWriteBuffer out_hashing(*out);
for (size_t i = 0; i < value.size(); ++i)
{
partition_key_sample.getByPosition(i).type->getDefaultSerialization()->serializeBinary(value[i], out_hashing, {});
}
out_hashing.next();
checksums.files["partition.dat"].file_size = out_hashing.count();
checksums.files["partition.dat"].file_hash = out_hashing.getHash();
out->preFinalize();
return out;
}
void MergeTreePartition::create(const StorageMetadataPtr & metadata_snapshot, Block block, size_t row, ContextPtr context)
{
if (!metadata_snapshot->hasPartitionKey())
return;
auto partition_key_names_and_types = executePartitionByExpression(metadata_snapshot, block, context);
value.resize(partition_key_names_and_types.size());
/// Executing partition_by expression adds new columns to passed block according to partition functions.
/// The block is passed by reference and is used afterwards. `moduloLegacy` needs to be substituted back
/// with just `modulo`, because it was a temporary substitution.
static constexpr auto modulo_legacy_function_name = "moduloLegacy";
size_t i = 0;
for (const auto & element : partition_key_names_and_types)
{
auto & partition_column = block.getByName(element.name);
if (element.name.starts_with(modulo_legacy_function_name))
partition_column.name = "modulo" + partition_column.name.substr(std::strlen(modulo_legacy_function_name));
partition_column.column->get(row, value[i++]);
}
}
NamesAndTypesList MergeTreePartition::executePartitionByExpression(const StorageMetadataPtr & metadata_snapshot, Block & block, ContextPtr context)
{
auto adjusted_partition_key = adjustPartitionKey(metadata_snapshot, context);
adjusted_partition_key.expression->execute(block);
return adjusted_partition_key.sample_block.getNamesAndTypesList();
}
KeyDescription MergeTreePartition::adjustPartitionKey(const StorageMetadataPtr & metadata_snapshot, ContextPtr context)
{
const auto & partition_key = metadata_snapshot->getPartitionKey();
if (!partition_key.definition_ast)
return partition_key;
ASTPtr ast_copy = partition_key.definition_ast->clone();
/// Implementation of modulo function was changed from 8bit result type to 16bit. For backward compatibility partition by expression is always
/// calculated according to previous version - `moduloLegacy`.
if (KeyDescription::moduloToModuloLegacyRecursive(ast_copy))
{
auto adjusted_partition_key = KeyDescription::getKeyFromAST(ast_copy, metadata_snapshot->columns, context);
return adjusted_partition_key;
}
return partition_key;
}
void MergeTreePartition::appendFiles(const MergeTreeData & storage, Strings& files)
{
auto metadata_snapshot = storage.getInMemoryMetadataPtr();
if (!metadata_snapshot->hasPartitionKey())
return;
files.push_back("partition.dat");
}
}