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17 lines
654 B
MySQL
17 lines
654 B
MySQL
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DROP TABLE IF EXISTS test.nullable_alter;
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CREATE TABLE test.nullable_alter (d Date DEFAULT '2000-01-01', x String) ENGINE = MergeTree(d, d, 1);
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INSERT INTO test.nullable_alter (x) VALUES ('Hello'), ('World');
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SELECT x FROM test.nullable_alter ORDER BY x;
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ALTER TABLE test.nullable_alter MODIFY COLUMN x Nullable(String);
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SELECT x FROM test.nullable_alter ORDER BY x;
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INSERT INTO test.nullable_alter (x) VALUES ('xyz'), (NULL);
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SELECT x FROM test.nullable_alter ORDER BY x NULLS FIRST;
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ALTER TABLE test.nullable_alter MODIFY COLUMN x Nullable(FixedString(5));
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SELECT x FROM test.nullable_alter ORDER BY x NULLS FIRST;
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DROP TABLE test.nullable_alter;
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