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18 lines
768 B
MySQL
18 lines
768 B
MySQL
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drop table if exists merge_tree;
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create table merge_tree ( CounterID UInt32, StartDate Date, Sign Int8, VisitID UInt64, UserID UInt64, StartTime DateTime, ClickLogID UInt64) ENGINE = CollapsingMergeTree(StartDate, intHash32(UserID), tuple(CounterID, StartDate, intHash32(UserID), VisitID, ClickLogID), 8192, Sign);
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insert into merge_tree values (1, '2013-09-19', 1, 0, 2, '2013-09-19 12:43:06', 3)
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alter table merge_tree add column dummy String after CounterID;
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describe table merge_tree;
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insert into merge_tree values (1, 'Hello, Alter Table!','2013-09-19', 1, 0, 2, '2013-09-19 12:43:06', 3)
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select CounterID, dummy from merge_tree where dummy <> '' limit 10;
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alter table merge_tree drop column dummy;
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describe table merge_tree;
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drop table merge_tree;
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