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@ -87,15 +87,19 @@ Block MergeTreeBaseBlockInputStream::readFromPart()
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if (!task.size_predictor)
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if (!task.size_predictor)
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return max_block_size_rows;
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return max_block_size_rows;
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/// Limit in rows, calculated by preferred_max_column_in_block_size_bytes. Can't be less than index_granularity.
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size_t rows_to_read = std::max(index_granularity, task.size_predictor->estimateNumRows(preferred_block_size_bytes));
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size_t rows_to_read = std::max(index_granularity, task.size_predictor->estimateNumRows(preferred_block_size_bytes));
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if (preferred_max_column_in_block_size_bytes)
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if (preferred_max_column_in_block_size_bytes)
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{
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{
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/// Limit in rows, calculated by preferred_max_column_in_block_size_bytes.
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size_t rows_to_read_for_max_size_column
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size_t rows_to_read_for_max_size_column
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= task.size_predictor->estimateNumRowsForMaxSizeColumn(preferred_max_column_in_block_size_bytes);
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= task.size_predictor->estimateNumRowsForMaxSizeColumn(preferred_max_column_in_block_size_bytes);
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double filtration_ratio = std::max(min_filtration_ratio, 1.0 - task.size_predictor->filtered_rows_ratio);
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double filtration_ratio = std::max(min_filtration_ratio, 1.0 - task.size_predictor->filtered_rows_ratio);
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size_t rows_to_read_for_max_size_column_with_filtration
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size_t rows_to_read_for_max_size_column_with_filtration
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= static_cast<size_t>(rows_to_read_for_max_size_column / filtration_ratio);
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= static_cast<size_t>(rows_to_read_for_max_size_column / filtration_ratio);
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/// If preferred_max_column_in_block_size_bytes is used, number of rows to read can be less than index_granularity.
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rows_to_read = std::min(rows_to_read, rows_to_read_for_max_size_column_with_filtration);
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rows_to_read = std::min(rows_to_read, rows_to_read_for_max_size_column_with_filtration);
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}
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}
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