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Oracle> Select to_number(‘123’) from dual;  -----         123;
              select to_char(33) from dual;----                      33;
Mysql> Select conv(‘123’,10,10); ----                123;
           Select cast(‘123’ as signed integer);---    123
          Select cast(‘-123’ as signed integer);---   -123
          select cast(33 as char(2) ); -------            33£»
          select char(33);--------------------              !;(ascll)
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2.       ËÄÉáÎåÈ뺯ÊýÇø±ð
Oracle> select floor(12.89*10)/10 from dual;--12.8
          select ceil(12.82*10)/10 from dual;--12.9
          select round(12.86*10)/10 from dual;--12.9
      select round(12.84*10)/10 from dual;--12.8
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GRANT ALL PRIVILEGES ON *.* TO 'root'@'%'IDENTIFIED BY 'password' WITH GRANT OPTION;
FLUSH RIVILEGES;
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SQL #1: select * from uchome_feed where uid in('0',501...) order by dateline desc limit 0,50;
SQL #2: select * from uchome_feed where uid in(0,501...) order by dateline desc limit 0,50;
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