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dbms: improving performance of String IN (set) (for graphite) [#METR-2944].

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This commit is contained in:
Alexey Milovidov 2015-02-13 04:18:28 +03:00
parent ea113f138f
commit dea75f4445
1 changed files with 12 additions and 1 deletions
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13
dbms/src/Interpreters/Set.cpp
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@ -472,12 +472,23 @@ void Set::executeOrdinary(const ConstColumnPlainPtrs & key_columns, ColumnUInt8:
const ColumnString::Offsets_t & offsets = column_string->getOffsets();
const ColumnString::Chars_t & data = column_string->getChars();
StringRef prev_key;
bool prev_result;
/// Для всех строчек
for (size_t i = 0; i < rows; ++i)
{
/// Строим ключ
StringRef ref(&data[i == 0 ? 0 : offsets[i - 1]], (i == 0 ? offsets[i] : (offsets[i] - offsets[i - 1])) - 1);
vec_res[i] = negative ^ (set.end() != set.find(ref));
if (i != 0 && ref == prev_key)
vec_res[i] = prev_result;
else
{
prev_result = negative ^ (set.end() != set.find(ref));
prev_key = ref;
vec_res[i] = prev_result;
}
}
}
else if (const ColumnFixedString * column_string = typeid_cast<const ColumnFixedString *>(&column))