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19 lines
800 B
SQL
19 lines
800 B
SQL
drop table if exists table_02152;
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create table table_02152 (a String, b LowCardinality(String)) engine = MergeTree order by a;
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insert into table_02152 values ('a_1', 'b_1') ('a_2', 'b_2') ('a_1', 'b_3') ('a_2', 'b_2');
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set count_distinct_optimization=true;
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select countDistinct(a) from table_02152;
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select countDistinct(b) from table_02152;
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select uniqExact(m) from (select number, (number / 2)::UInt64 as m from numbers(10));
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select uniqExact(x) from numbers(10) group by number % 2 as x;
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set count_distinct_optimization=false;
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select countDistinct(a) from table_02152;
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select countDistinct(b) from table_02152;
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select uniqExact(m) from (select number, (number / 2)::UInt64 as m from numbers(10));
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select uniqExact(x) from numbers(10) group by number % 2 as x;
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drop table if exists table_02152;
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