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23 lines
733 B
SQL
23 lines
733 B
SQL
-- max_memory_usage = 10000000000 (10 GB default)
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-- Intel® Xeon® E5-1650 v3 Hexadcore 128 GB DDR4 ECC
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-- Estimated time: ~ 250 seconds
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-- Read rows: ~ 272 000 000
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SELECT
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key,
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uniqState(uuid_1) uuid_1_st,
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uniqState(uuid_2) uuid_2_st,
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uniqState(uuid_3) uuid_3_st
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FROM (
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SELECT
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rand64() value,
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toString(value) value_str,
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UUIDNumToString(toFixedString(substring(value_str, 1, 16), 16)) uuid_1, -- Any UUID
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UUIDNumToString(toFixedString(substring(value_str, 2, 16), 16)) uuid_2, -- More memory
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UUIDNumToString(toFixedString(substring(value_str, 3, 16), 16)) uuid_3, -- And more memory
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modulo(value, 5000000) key -- Cardinality in my case
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FROM numbers(550000000)
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)
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GROUP BY
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key
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LIMIT 100;
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