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½á¹û: 2004 3rd August 03:35:48 2004[/code]

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[code]alter table tb_name change old_col new_col definition...[/code]

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[code]select @var1:=a1+a2 as a_sum,@var2:=b1+b2 as b_sum,@var1+@var2 as total_sum from test_table xxx;[/code]

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[code]update rule set enable = if('0' = enable,'1','0') where xxx;

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