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1.Ìõ¼þ¿ØÖÆ
1.1 if .. then .. end if
if Ìõ¼þ then
    Óï¾ä¶Î£»
end if;
1.2 if .. then .. else .. end if
if Ìõ¼þ then
    Óï¾ä¶Î£»
else 
    Óï¾ä¶Î£»
end if;
1.3 ifǶÌ×
2.Ñ­»·¿ØÖÆ
2.1 loop .. exit .. end loop
loop  
    Ñ­»·Óï¾ä¶Î;
    if Ìõ¼þÓï¾ä then
       Óï¾ä¶Î; 
       exit;
    else
       Óï¾ä¶Î;
    end if
end loop;
2.2 loop .. exit .. when .. end loop
loop
    Óï¾ä¶Î;
    exit when Ìõ¼þÓï¾ä;
end loop;
2.3 while .. loop .. end loop
while Ìõ¼þ loop
     Óï¾ä¶Î;
end loop;
2.4 for .. in .. loop.. end
for Ñ­»·±äÁ¿ in [reverse] Ñ­»·Ï½ç..Ñ­»·ÉϽç loop
     Óï¾ä¶Î;
end loop;
×¢Ò⣺reverse±íʾ´ÓºóÍùÇ°Ñ­»·£¬Ñ­»·ÉÏϽ粻±ä
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set serveroutput on
declare
  i integer:=0;
begin
  for i in reverse 1..10 loop
    dbms_output.put_line('i µÄÖµ£º' || to_char(i));
  end loop;    
end;
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select sum(quantity) total ,price_water,price_pollute from pay_water where time_pay >='2010-02-01 00:00:00.000' and time_pay <'2010-02-28 23:59:59.000'
group by price_water,price_pollute
µÚ¶þ²½ ......

linq to sql ÖдÓdbmlÎļþÖд´½¨Êý¾Ý¿â

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        Ñо¿ÁËÒ»¶ÎÊ ......

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check_expression
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PL/SQLѧϰ±Ê¼ÇÒ»


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