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27 lines
968 B
SQL
27 lines
968 B
SQL
select '--------';
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SELECT arrayJoin([0, 1, 3, NULL]) AS x, x = 0, if(x = 0, 'x=0', 'x<>0') ORDER BY x;
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select '--------';
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drop table if exists mutation_delete_null_rows;
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CREATE TABLE mutation_delete_null_rows
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(
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`EventDate` Date,
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`CounterID` Nullable(String),
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`UserID` Nullable(UInt32)
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)
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ENGINE = MergeTree()
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ORDER BY EventDate;
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INSERT INTO mutation_delete_null_rows VALUES ('2020-01-01', '', 2)('2020-01-02', 'aaa', 0);
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INSERT INTO mutation_delete_null_rows VALUES ('2020-01-03', '', 2)('2020-01-04', '', 2)('2020-01-05', NULL, 2)('2020-01-06', 'aaa', 0)('2020-01-07', 'aaa', 0)('2020-01-08', 'aaa', NULL);
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SELECT *,UserID = 0 as UserIDEquals0, if(UserID = 0, 'delete', 'leave') as verdict FROM mutation_delete_null_rows ORDER BY EventDate;
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ALTER TABLE mutation_delete_null_rows DELETE WHERE UserID = 0 SETTINGS mutations_sync=1;
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select '--------';
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SELECT * FROM mutation_delete_null_rows ORDER BY EventDate;
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drop table mutation_delete_null_rows;
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