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20 lines
815 B
MySQL
20 lines
815 B
MySQL
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set allow_experimental_low_cardinality_type = 1;
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create table test.tab (a String, b LowCardinality(UInt32)) engine = MergeTree order by a;
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insert into test.tab values ('a', 1);
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select *, toTypeName(b) from test.tab;
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alter table test.tab modify column b UInt32;
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select *, toTypeName(b) from test.tab;
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alter table test.tab modify column b LowCardinality(UInt32);
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select *, toTypeName(b) from test.tab;
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alter table test.tab modify column b StringWithDictionary;
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select *, toTypeName(b) from test.tab;
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alter table test.tab modify column b LowCardinality(UInt32);
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select *, toTypeName(b) from test.tab;
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alter table test.tab modify column b String;
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select *, toTypeName(b) from test.tab;
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alter table test.tab modify column b LowCardinality(UInt32);
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select *, toTypeName(b) from test.tab;
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drop table if exists test.tab;
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