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l  S£ºselect abs(-1) value
l  O£ºselect abs(-1) value from dual
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l  S£ºselect ceiling(-001) value 
l  O£ºselect ceil(-001)   value from dual
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l  S£ºselect floor(-001) value   
l  O£ºselect floor(-001) value from dual
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l  S£ºselect cast(-002 as int)   value  
l  O£ºselect trunc(-002) value from dual 
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l  S£ºselect round(23456,4) value     23460
l  O£ºselect round(23456,4) value from dual 2346
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l  S£ºselect Exp(1) value          l  O£ºselect Exp(1) value from dual  
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l  S£ºselect log(7182818284590451) value      
l  O£ºselect ln(7182818284590451) value from dual;  
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l  S£ºselect log10(10) value         
l  O£ºselect log(10,10) value from dual;   
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l  S£ºselect SQUARE(4) value   
l  O£ºselect power(4,2) value from dual  
¢âȡƽ·½¸ù l  S£ºselect SQRT(4) value   
l  O£ºselect SQRT(4) value from dual  
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l  S£ºselect power(3,4) value      
l  O£ºselect power(3,4) value from dual  
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l  S£ºselect rand() value  
l  O£ºselect sys.dbms_random.value(0,1) value from dual;
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l  S£ºselect sign(-8) value    -1
l  O£ºselect sign(-8) value from dual  -1
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OracleµÄ¼¯ºÏÔËËã·û

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1      1      2
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