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Oracle???????

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?????Microsoft Windows XP [?? 5.1.2600]

?????SunOS 5.9 [Solaris 9]

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SQL????

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CREATE TABLE test (x char, y VARCHAR2(10)) tablespace users;

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DESCRIBE test;

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- x: CHAR(1) - ?????????????? - ????- y: VARCHAR2(10) - ?????????????? - ????

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ALTER TABLE test MODIFY (x CHAR(10));

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INSERT INTO test VALUES('a', 'b');

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SELECT * FROM test WHERE x = 'a';

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x | y  a | b

SELECT * FROM test WHERE y = 'b';

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x | y  a | b

SELECT * FROM test WHERE y > 'b';

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x | y  a | b

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