ClickHouse/src/Storages/MergeTree/MergeTreeIndexFullText.cpp

826 lines
30 KiB
C++

#include <Storages/MergeTree/MergeTreeIndexFullText.h>
#include <Common/StringUtils/StringUtils.h>
#include <Common/UTF8Helpers.h>
#include <DataTypes/DataTypesNumber.h>
#include <IO/WriteHelpers.h>
#include <IO/ReadHelpers.h>
#include <Interpreters/ExpressionActions.h>
#include <Interpreters/ExpressionAnalyzer.h>
#include <Interpreters/SyntaxAnalyzer.h>
#include <Interpreters/misc.h>
#include <Storages/MergeTree/MergeTreeData.h>
#include <Storages/MergeTree/RPNBuilder.h>
#include <Parsers/ASTIdentifier.h>
#include <Parsers/ASTLiteral.h>
#include <Parsers/ASTSubquery.h>
#include <Poco/Logger.h>
#include <boost/algorithm/string.hpp>
#if defined(__SSE2__)
#include <immintrin.h>
#if defined(__SSE4_2__)
#include <nmmintrin.h>
#endif
#endif
namespace DB
{
namespace ErrorCodes
{
extern const int LOGICAL_ERROR;
extern const int INCORRECT_QUERY;
}
/// Adds all tokens from string to bloom filter.
static void stringToBloomFilter(
const char * data, size_t size, const std::unique_ptr<ITokenExtractor> & token_extractor, BloomFilter & bloom_filter)
{
size_t cur = 0;
size_t token_start = 0;
size_t token_len = 0;
while (cur < size && token_extractor->next(data, size, &cur, &token_start, &token_len))
bloom_filter.add(data + token_start, token_len);
}
/// Adds all tokens from like pattern string to bloom filter. (Because like pattern can contain `\%` and `\_`.)
static void likeStringToBloomFilter(
const String & data, const std::unique_ptr<ITokenExtractor> & token_extractor, BloomFilter & bloom_filter)
{
size_t cur = 0;
String token;
while (cur < data.size() && token_extractor->nextLike(data, &cur, token))
bloom_filter.add(token.c_str(), token.size());
}
/// Unified condition for equals, startsWith and endsWith
bool MergeTreeConditionFullText::createFunctionEqualsCondition(RPNElement & out, const Field & value, const MergeTreeIndexFullText & idx)
{
out.function = RPNElement::FUNCTION_EQUALS;
out.bloom_filter = std::make_unique<BloomFilter>(
idx.bloom_filter_size, idx.bloom_filter_hashes, idx.seed);
const auto & str = value.get<String>();
stringToBloomFilter(str.c_str(), str.size(), idx.token_extractor_func, *out.bloom_filter);
return true;
}
MergeTreeIndexGranuleFullText::MergeTreeIndexGranuleFullText(const MergeTreeIndexFullText & index_)
: index(index_)
, bloom_filters(
index.columns.size(), BloomFilter(index.bloom_filter_size, index.bloom_filter_hashes, index.seed))
, has_elems(false) {}
void MergeTreeIndexGranuleFullText::serializeBinary(WriteBuffer & ostr) const
{
if (empty())
throw Exception("Attempt to write empty minmax index " + backQuote(index.name), ErrorCodes::LOGICAL_ERROR);
for (const auto & bloom_filter : bloom_filters)
ostr.write(reinterpret_cast<const char *>(bloom_filter.getFilter().data()), index.bloom_filter_size);
}
void MergeTreeIndexGranuleFullText::deserializeBinary(ReadBuffer & istr)
{
for (auto & bloom_filter : bloom_filters)
{
istr.read(reinterpret_cast<char *>(bloom_filter.getFilter().data()), index.bloom_filter_size);
}
has_elems = true;
}
MergeTreeIndexAggregatorFullText::MergeTreeIndexAggregatorFullText(const MergeTreeIndexFullText & index_)
: index(index_), granule(std::make_shared<MergeTreeIndexGranuleFullText>(index)) {}
MergeTreeIndexGranulePtr MergeTreeIndexAggregatorFullText::getGranuleAndReset()
{
auto new_granule = std::make_shared<MergeTreeIndexGranuleFullText>(index);
new_granule.swap(granule);
return new_granule;
}
void MergeTreeIndexAggregatorFullText::update(const Block & block, size_t * pos, size_t limit)
{
if (*pos >= block.rows())
throw Exception(
"The provided position is not less than the number of block rows. Position: "
+ toString(*pos) + ", Block rows: " + toString(block.rows()) + ".", ErrorCodes::LOGICAL_ERROR);
size_t rows_read = std::min(limit, block.rows() - *pos);
for (size_t col = 0; col < index.columns.size(); ++col)
{
const auto & column = block.getByName(index.columns[col]).column;
for (size_t i = 0; i < rows_read; ++i)
{
auto ref = column->getDataAt(*pos + i);
stringToBloomFilter(ref.data, ref.size, index.token_extractor_func, granule->bloom_filters[col]);
}
}
granule->has_elems = true;
*pos += rows_read;
}
MergeTreeConditionFullText::MergeTreeConditionFullText(
const SelectQueryInfo & query_info,
const Context & context,
const MergeTreeIndexFullText & index_) : index(index_), prepared_sets(query_info.sets)
{
rpn = std::move(
RPNBuilder<RPNElement>(
query_info, context,
[this] (const ASTPtr & node, const Context & /* context */, Block & block_with_constants, RPNElement & out) -> bool
{
return this->atomFromAST(node, block_with_constants, out);
}).extractRPN());
}
bool MergeTreeConditionFullText::alwaysUnknownOrTrue() const
{
/// Check like in KeyCondition.
std::vector<bool> rpn_stack;
for (const auto & element : rpn)
{
if (element.function == RPNElement::FUNCTION_UNKNOWN
|| element.function == RPNElement::ALWAYS_TRUE)
{
rpn_stack.push_back(true);
}
else if (element.function == RPNElement::FUNCTION_EQUALS
|| element.function == RPNElement::FUNCTION_NOT_EQUALS
|| element.function == RPNElement::FUNCTION_IN
|| element.function == RPNElement::FUNCTION_NOT_IN
|| element.function == RPNElement::FUNCTION_MULTI_SEARCH
|| element.function == RPNElement::ALWAYS_FALSE)
{
rpn_stack.push_back(false);
}
else if (element.function == RPNElement::FUNCTION_NOT)
{
// do nothing
}
else if (element.function == RPNElement::FUNCTION_AND)
{
auto arg1 = rpn_stack.back();
rpn_stack.pop_back();
auto arg2 = rpn_stack.back();
rpn_stack.back() = arg1 && arg2;
}
else if (element.function == RPNElement::FUNCTION_OR)
{
auto arg1 = rpn_stack.back();
rpn_stack.pop_back();
auto arg2 = rpn_stack.back();
rpn_stack.back() = arg1 || arg2;
}
else
throw Exception("Unexpected function type in KeyCondition::RPNElement", ErrorCodes::LOGICAL_ERROR);
}
return rpn_stack[0];
}
bool MergeTreeConditionFullText::mayBeTrueOnGranule(MergeTreeIndexGranulePtr idx_granule) const
{
std::shared_ptr<MergeTreeIndexGranuleFullText> granule
= std::dynamic_pointer_cast<MergeTreeIndexGranuleFullText>(idx_granule);
if (!granule)
throw Exception(
"BloomFilter index condition got a granule with the wrong type.", ErrorCodes::LOGICAL_ERROR);
/// Check like in KeyCondition.
std::vector<BoolMask> rpn_stack;
for (const auto & element : rpn)
{
if (element.function == RPNElement::FUNCTION_UNKNOWN)
{
rpn_stack.emplace_back(true, true);
}
else if (element.function == RPNElement::FUNCTION_EQUALS
|| element.function == RPNElement::FUNCTION_NOT_EQUALS)
{
rpn_stack.emplace_back(granule->bloom_filters[element.key_column].contains(*element.bloom_filter), true);
if (element.function == RPNElement::FUNCTION_NOT_EQUALS)
rpn_stack.back() = !rpn_stack.back();
}
else if (element.function == RPNElement::FUNCTION_IN
|| element.function == RPNElement::FUNCTION_NOT_IN)
{
std::vector<bool> result(element.set_bloom_filters.back().size(), true);
for (size_t column = 0; column < element.set_key_position.size(); ++column)
{
const size_t key_idx = element.set_key_position[column];
const auto & bloom_filters = element.set_bloom_filters[column];
for (size_t row = 0; row < bloom_filters.size(); ++row)
result[row] = result[row] && granule->bloom_filters[key_idx].contains(bloom_filters[row]);
}
rpn_stack.emplace_back(
std::find(std::cbegin(result), std::cend(result), true) != std::end(result), true);
if (element.function == RPNElement::FUNCTION_NOT_IN)
rpn_stack.back() = !rpn_stack.back();
}
else if (element.function == RPNElement::FUNCTION_MULTI_SEARCH)
{
std::vector<bool> result(element.set_bloom_filters.back().size(), true);
const auto & bloom_filters = element.set_bloom_filters[0];
for (size_t row = 0; row < bloom_filters.size(); ++row)
result[row] = result[row] && granule->bloom_filters[element.key_column].contains(bloom_filters[row]);
rpn_stack.emplace_back(
std::find(std::cbegin(result), std::cend(result), true) != std::end(result), true);
}
else if (element.function == RPNElement::FUNCTION_NOT)
{
rpn_stack.back() = !rpn_stack.back();
}
else if (element.function == RPNElement::FUNCTION_AND)
{
auto arg1 = rpn_stack.back();
rpn_stack.pop_back();
auto arg2 = rpn_stack.back();
rpn_stack.back() = arg1 & arg2;
}
else if (element.function == RPNElement::FUNCTION_OR)
{
auto arg1 = rpn_stack.back();
rpn_stack.pop_back();
auto arg2 = rpn_stack.back();
rpn_stack.back() = arg1 | arg2;
}
else if (element.function == RPNElement::ALWAYS_FALSE)
{
rpn_stack.emplace_back(false, true);
}
else if (element.function == RPNElement::ALWAYS_TRUE)
{
rpn_stack.emplace_back(true, false);
}
else
throw Exception("Unexpected function type in BloomFilterCondition::RPNElement", ErrorCodes::LOGICAL_ERROR);
}
if (rpn_stack.size() != 1)
throw Exception("Unexpected stack size in BloomFilterCondition::mayBeTrueOnGranule", ErrorCodes::LOGICAL_ERROR);
return rpn_stack[0].can_be_true;
}
bool MergeTreeConditionFullText::getKey(const ASTPtr & node, size_t & key_column_num)
{
auto it = std::find(index.columns.begin(), index.columns.end(), node->getColumnName());
if (it == index.columns.end())
return false;
key_column_num = static_cast<size_t>(it - index.columns.begin());
return true;
}
bool MergeTreeConditionFullText::atomFromAST(
const ASTPtr & node, Block & block_with_constants, RPNElement & out)
{
Field const_value;
DataTypePtr const_type;
if (const auto * func = typeid_cast<const ASTFunction *>(node.get()))
{
const ASTs & args = typeid_cast<const ASTExpressionList &>(*func->arguments).children;
if (args.size() != 2)
return false;
size_t key_arg_pos; /// Position of argument with key column (non-const argument)
size_t key_column_num = -1; /// Number of a key column (inside key_column_names array)
const auto & func_name = func->name;
if (functionIsInOrGlobalInOperator(func_name) && tryPrepareSetBloomFilter(args, out))
{
key_arg_pos = 0;
}
else if (KeyCondition::getConstant(args[1], block_with_constants, const_value, const_type) && getKey(args[0], key_column_num))
{
key_arg_pos = 0;
}
else if (KeyCondition::getConstant(args[0], block_with_constants, const_value, const_type) && getKey(args[1], key_column_num))
{
key_arg_pos = 1;
}
else
return false;
if (const_type && const_type->getTypeId() != TypeIndex::String
&& const_type->getTypeId() != TypeIndex::FixedString
&& const_type->getTypeId() != TypeIndex::Array)
{
return false;
}
if (key_arg_pos == 1 && (func_name != "equals" || func_name != "notEquals"))
return false;
else if (!index.token_extractor_func->supportLike() && (func_name == "like" || func_name == "notLike"))
return false;
if (func_name == "notEquals")
{
out.key_column = key_column_num;
out.function = RPNElement::FUNCTION_NOT_EQUALS;
out.bloom_filter = std::make_unique<BloomFilter>(
index.bloom_filter_size, index.bloom_filter_hashes, index.seed);
const auto & str = const_value.get<String>();
stringToBloomFilter(str.c_str(), str.size(), index.token_extractor_func, *out.bloom_filter);
return true;
}
else if (func_name == "equals")
{
out.key_column = key_column_num;
return createFunctionEqualsCondition(out, const_value, index);
}
else if (func_name == "like")
{
out.key_column = key_column_num;
out.function = RPNElement::FUNCTION_EQUALS;
out.bloom_filter = std::make_unique<BloomFilter>(
index.bloom_filter_size, index.bloom_filter_hashes, index.seed);
const auto & str = const_value.get<String>();
likeStringToBloomFilter(str, index.token_extractor_func, *out.bloom_filter);
return true;
}
else if (func_name == "notLike")
{
out.key_column = key_column_num;
out.function = RPNElement::FUNCTION_NOT_EQUALS;
out.bloom_filter = std::make_unique<BloomFilter>(
index.bloom_filter_size, index.bloom_filter_hashes, index.seed);
const auto & str = const_value.get<String>();
likeStringToBloomFilter(str, index.token_extractor_func, *out.bloom_filter);
return true;
}
else if (func_name == "hasToken")
{
out.key_column = key_column_num;
out.function = RPNElement::FUNCTION_EQUALS;
out.bloom_filter = std::make_unique<BloomFilter>(
index.bloom_filter_size, index.bloom_filter_hashes, index.seed);
const auto & str = const_value.get<String>();
stringToBloomFilter(str.c_str(), str.size(), index.token_extractor_func, *out.bloom_filter);
return true;
}
else if (func_name == "startsWith")
{
out.key_column = key_column_num;
return createFunctionEqualsCondition(out, const_value, index);
}
else if (func_name == "endsWith")
{
out.key_column = key_column_num;
return createFunctionEqualsCondition(out, const_value, index);
}
else if (func_name == "multiSearchAny")
{
out.key_column = key_column_num;
out.function = RPNElement::FUNCTION_MULTI_SEARCH;
/// 2d vector is not needed here but is used because already exists for FUNCTION_IN
std::vector<std::vector<BloomFilter>> bloom_filters;
bloom_filters.emplace_back();
for (const auto & element : const_value.get<Array>())
{
if (element.getType() != Field::Types::String)
return false;
bloom_filters.back().emplace_back(index.bloom_filter_size, index.bloom_filter_hashes, index.seed);
const auto & str = element.get<String>();
stringToBloomFilter(str.c_str(), str.size(), index.token_extractor_func, bloom_filters.back().back());
}
out.set_bloom_filters = std::move(bloom_filters);
return true;
}
else if (func_name == "notIn")
{
out.key_column = key_column_num;
out.function = RPNElement::FUNCTION_NOT_IN;
return true;
}
else if (func_name == "in")
{
out.key_column = key_column_num;
out.function = RPNElement::FUNCTION_IN;
return true;
}
return false;
}
else if (KeyCondition::getConstant(node, block_with_constants, const_value, const_type))
{
/// Check constant like in KeyCondition
if (const_value.getType() == Field::Types::UInt64
|| const_value.getType() == Field::Types::Int64
|| const_value.getType() == Field::Types::Float64)
{
/// Zero in all types is represented in memory the same way as in UInt64.
out.function = const_value.get<UInt64>()
? RPNElement::ALWAYS_TRUE
: RPNElement::ALWAYS_FALSE;
return true;
}
}
return false;
}
bool MergeTreeConditionFullText::tryPrepareSetBloomFilter(
const ASTs & args,
RPNElement & out)
{
const ASTPtr & left_arg = args[0];
const ASTPtr & right_arg = args[1];
std::vector<KeyTuplePositionMapping> key_tuple_mapping;
DataTypes data_types;
const auto * left_arg_tuple = typeid_cast<const ASTFunction *>(left_arg.get());
if (left_arg_tuple && left_arg_tuple->name == "tuple")
{
const auto & tuple_elements = left_arg_tuple->arguments->children;
for (size_t i = 0; i < tuple_elements.size(); ++i)
{
size_t key = 0;
if (getKey(tuple_elements[i], key))
{
key_tuple_mapping.emplace_back(i, key);
data_types.push_back(index.data_types[key]);
}
}
}
else
{
size_t key = 0;
if (getKey(left_arg, key))
{
key_tuple_mapping.emplace_back(0, key);
data_types.push_back(index.data_types[key]);
}
}
if (key_tuple_mapping.empty())
return false;
PreparedSetKey set_key;
if (typeid_cast<const ASTSubquery *>(right_arg.get()) || typeid_cast<const ASTIdentifier *>(right_arg.get()))
set_key = PreparedSetKey::forSubquery(*right_arg);
else
set_key = PreparedSetKey::forLiteral(*right_arg, data_types);
auto set_it = prepared_sets.find(set_key);
if (set_it == prepared_sets.end())
return false;
const SetPtr & prepared_set = set_it->second;
if (!prepared_set->hasExplicitSetElements())
return false;
for (const auto & data_type : prepared_set->getDataTypes())
if (data_type->getTypeId() != TypeIndex::String && data_type->getTypeId() != TypeIndex::FixedString)
return false;
std::vector<std::vector<BloomFilter>> bloom_filters;
std::vector<size_t> key_position;
Columns columns = prepared_set->getSetElements();
for (const auto & elem : key_tuple_mapping)
{
bloom_filters.emplace_back();
key_position.push_back(elem.key_index);
size_t tuple_idx = elem.tuple_index;
const auto & column = columns[tuple_idx];
for (size_t row = 0; row < prepared_set->getTotalRowCount(); ++row)
{
bloom_filters.back().emplace_back(index.bloom_filter_size, index.bloom_filter_hashes, index.seed);
auto ref = column->getDataAt(row);
stringToBloomFilter(ref.data, ref.size, index.token_extractor_func, bloom_filters.back().back());
}
}
out.set_key_position = std::move(key_position);
out.set_bloom_filters = std::move(bloom_filters);
return true;
}
MergeTreeIndexGranulePtr MergeTreeIndexFullText::createIndexGranule() const
{
return std::make_shared<MergeTreeIndexGranuleFullText>(*this);
}
MergeTreeIndexAggregatorPtr MergeTreeIndexFullText::createIndexAggregator() const
{
return std::make_shared<MergeTreeIndexAggregatorFullText>(*this);
}
MergeTreeIndexConditionPtr MergeTreeIndexFullText::createIndexCondition(
const SelectQueryInfo & query, const Context & context) const
{
return std::make_shared<MergeTreeConditionFullText>(query, context, *this);
};
bool MergeTreeIndexFullText::mayBenefitFromIndexForIn(const ASTPtr & node) const
{
return std::find(std::cbegin(columns), std::cend(columns), node->getColumnName()) != std::cend(columns);
}
bool NgramTokenExtractor::next(const char * data, size_t len, size_t * pos, size_t * token_start, size_t * token_len) const
{
*token_start = *pos;
*token_len = 0;
size_t code_points = 0;
for (; code_points < n && *token_start + *token_len < len; ++code_points)
{
size_t sz = UTF8::seqLength(static_cast<UInt8>(data[*token_start + *token_len]));
*token_len += sz;
}
*pos += UTF8::seqLength(static_cast<UInt8>(data[*pos]));
return code_points == n;
}
bool NgramTokenExtractor::nextLike(const String & str, size_t * pos, String & token) const
{
token.clear();
size_t code_points = 0;
bool escaped = false;
for (size_t i = *pos; i < str.size();)
{
if (escaped && (str[i] == '%' || str[i] == '_' || str[i] == '\\'))
{
token += str[i];
++code_points;
escaped = false;
++i;
}
else if (!escaped && (str[i] == '%' || str[i] == '_'))
{
/// This token is too small, go to the next.
token.clear();
code_points = 0;
escaped = false;
*pos = ++i;
}
else if (!escaped && str[i] == '\\')
{
escaped = true;
++i;
}
else
{
const size_t sz = UTF8::seqLength(static_cast<UInt8>(str[i]));
for (size_t j = 0; j < sz; ++j)
token += str[i + j];
i += sz;
++code_points;
escaped = false;
}
if (code_points == n)
{
*pos += UTF8::seqLength(static_cast<UInt8>(str[*pos]));
return true;
}
}
return false;
}
bool SplitTokenExtractor::next(const char * data, size_t len, size_t * pos, size_t * token_start, size_t * token_len) const
{
*token_start = *pos;
*token_len = 0;
while (*pos < len)
{
#if defined(__SSE2__)
// NOTE: we assume that `data` string is padded from the right with 15 bytes.
const __m128i haystack = _mm_loadu_si128(reinterpret_cast<const __m128i *>(data + *pos));
const size_t haystack_length = 16;
#if defined(__SSE4_2__)
// With the help of https://www.strchr.com/strcmp_and_strlen_using_sse_4.2
const auto alnum_chars_ranges = _mm_set_epi8(0, 0, 0, 0, 0, 0, 0, 0,
'\xFF', '\x80', 'z', 'a', 'Z', 'A', '9', '0');
// Every bit represents if `haystack` character is in the ranges (1) or not (0)
const int result_bitmask = _mm_cvtsi128_si32(_mm_cmpestrm(alnum_chars_ranges, 8, haystack, haystack_length, _SIDD_CMP_RANGES));
#else
// NOTE: -1 and +1 required since SSE2 has no `>=` and `<=` instructions on packed 8-bit integers (epi8).
const auto number_begin = _mm_set1_epi8('0' - 1);
const auto number_end = _mm_set1_epi8('9' + 1);
const auto alpha_lower_begin = _mm_set1_epi8('a' - 1);
const auto alpha_lower_end = _mm_set1_epi8('z' + 1);
const auto alpha_upper_begin = _mm_set1_epi8('A' - 1);
const auto alpha_upper_end = _mm_set1_epi8('Z' + 1);
const auto zero = _mm_set1_epi8(0);
// every bit represents if `haystack` character `c` statisfies condition:
// (c < 0) || (c > '0' - 1 && c < '9' + 1) || (c > 'a' - 1 && c < 'z' + 1) || (c > 'A' - 1 && c < 'Z' + 1)
// < 0 since _mm_cmplt_epi8 threats chars as SIGNED, and so all chars > 0x80 are negative.
const int result_bitmask = _mm_movemask_epi8(_mm_or_si128(_mm_or_si128(_mm_or_si128(
_mm_cmplt_epi8(haystack, zero),
_mm_and_si128(_mm_cmpgt_epi8(haystack, number_begin), _mm_cmplt_epi8(haystack, number_end))),
_mm_and_si128(_mm_cmpgt_epi8(haystack, alpha_lower_begin), _mm_cmplt_epi8(haystack, alpha_lower_end))),
_mm_and_si128(_mm_cmpgt_epi8(haystack, alpha_upper_begin), _mm_cmplt_epi8(haystack, alpha_upper_end))));
#endif
if (result_bitmask == 0)
{
if (*token_len != 0)
// end of token started on previous haystack
return true;
*pos += haystack_length;
continue;
}
const auto token_start_pos_in_current_haystack = getTrailingZeroBitsUnsafe(result_bitmask);
if (*token_len == 0)
// new token
*token_start = *pos + token_start_pos_in_current_haystack;
else if (token_start_pos_in_current_haystack != 0)
// end of token starting in one of previous haystacks
return true;
const auto token_bytes_in_current_haystack = getTrailingZeroBitsUnsafe(~(result_bitmask >> token_start_pos_in_current_haystack));
*token_len += token_bytes_in_current_haystack;
*pos += token_start_pos_in_current_haystack + token_bytes_in_current_haystack;
if (token_start_pos_in_current_haystack + token_bytes_in_current_haystack == haystack_length)
// check if there are leftovers in next `haystack`
continue;
break;
#else
if (isASCII(data[*pos]) && !isAlphaNumericASCII(data[*pos]))
{
/// Finish current token if any
if (*token_len > 0)
return true;
*token_start = ++*pos;
}
else
{
/// Note that UTF-8 sequence is completely consisted of non-ASCII bytes.
++*pos;
++*token_len;
}
#endif
}
#if defined(__SSE2__)
// Could happen only if string is not padded with zeroes, and we accidentally hopped over end of data.
if (*token_start > len)
return false;
*token_len = std::min(len - *token_start, *token_len);
#endif
return *token_len > 0;
}
bool SplitTokenExtractor::nextLike(const String & str, size_t * pos, String & token) const
{
token.clear();
bool bad_token = false; // % or _ before token
bool escaped = false;
while (*pos < str.size())
{
if (!escaped && (str[*pos] == '%' || str[*pos] == '_'))
{
token.clear();
bad_token = true;
++*pos;
}
else if (!escaped && str[*pos] == '\\')
{
escaped = true;
++*pos;
}
else if (isASCII(str[*pos]) && !isAlphaNumericASCII(str[*pos]))
{
if (!bad_token && !token.empty())
return true;
token.clear();
bad_token = false;
escaped = false;
++*pos;
}
else
{
const size_t sz = UTF8::seqLength(static_cast<UInt8>(str[*pos]));
for (size_t j = 0; j < sz; ++j)
{
token += str[*pos];
++*pos;
}
escaped = false;
}
}
return !bad_token && !token.empty();
}
std::unique_ptr<IMergeTreeIndex> bloomFilterIndexCreator(
const NamesAndTypesList & new_columns,
std::shared_ptr<ASTIndexDeclaration> node,
const Context & context,
bool /*attach*/)
{
if (node->name.empty())
throw Exception("Index must have unique name", ErrorCodes::INCORRECT_QUERY);
ASTPtr expr_list = MergeTreeData::extractKeyExpressionList(node->expr->clone());
auto syntax = SyntaxAnalyzer(context).analyze(expr_list, new_columns);
auto index_expr = ExpressionAnalyzer(expr_list, syntax, context).getActions(false);
auto sample = ExpressionAnalyzer(expr_list, syntax, context)
.getActions(true)->getSampleBlock();
Names columns;
DataTypes data_types;
for (size_t i = 0; i < expr_list->children.size(); ++i)
{
const auto & column = sample.getByPosition(i);
columns.emplace_back(column.name);
data_types.emplace_back(column.type);
if (data_types.back()->getTypeId() != TypeIndex::String
&& data_types.back()->getTypeId() != TypeIndex::FixedString)
throw Exception("Bloom filter index can be used only with `String` or `FixedString` column.", ErrorCodes::INCORRECT_QUERY);
}
boost::algorithm::to_lower(node->type->name);
if (node->type->name == NgramTokenExtractor::getName())
{
if (!node->type->arguments || node->type->arguments->children.size() != 4)
throw Exception("`ngrambf` index must have exactly 4 arguments.", ErrorCodes::INCORRECT_QUERY);
size_t n = typeid_cast<const ASTLiteral &>(
*node->type->arguments->children[0]).value.get<size_t>();
size_t bloom_filter_size = typeid_cast<const ASTLiteral &>(
*node->type->arguments->children[1]).value.get<size_t>();
size_t bloom_filter_hashes = typeid_cast<const ASTLiteral &>(
*node->type->arguments->children[2]).value.get<size_t>();
size_t seed = typeid_cast<const ASTLiteral &>(
*node->type->arguments->children[3]).value.get<size_t>();
auto tokenizer = std::make_unique<NgramTokenExtractor>(n);
return std::make_unique<MergeTreeIndexFullText>(
node->name, std::move(index_expr), columns, data_types, sample, node->granularity,
bloom_filter_size, bloom_filter_hashes, seed, std::move(tokenizer));
}
else if (node->type->name == SplitTokenExtractor::getName())
{
if (!node->type->arguments || node->type->arguments->children.size() != 3)
throw Exception("`tokenbf` index must have exactly 3 arguments.", ErrorCodes::INCORRECT_QUERY);
size_t bloom_filter_size = typeid_cast<const ASTLiteral &>(
*node->type->arguments->children[0]).value.get<size_t>();
size_t bloom_filter_hashes = typeid_cast<const ASTLiteral &>(
*node->type->arguments->children[1]).value.get<size_t>();
size_t seed = typeid_cast<const ASTLiteral &>(
*node->type->arguments->children[2]).value.get<size_t>();
auto tokenizer = std::make_unique<SplitTokenExtractor>();
return std::make_unique<MergeTreeIndexFullText>(
node->name, std::move(index_expr), columns, data_types, sample, node->granularity,
bloom_filter_size, bloom_filter_hashes, seed, std::move(tokenizer));
}
else
{
throw Exception("Unknown index type: " + backQuote(node->name), ErrorCodes::LOGICAL_ERROR);
}
}
}