oracle数据库判断表是否存在，存在删除，并创建新表

-判断表是否存在，存在就删除

declare

 v_exists number;

begin

    selectcount(*)intov_existsfromuser_tableswheretable_name = 'LLT_CONSUMERPVSHIELDRECORD';

    if v_exists > 0 then

    executeimmediate'drop table LLT_CONSUMERPVSHIELDRECORD';

    endif;

        

end;

/

--创建PV屏蔽值记录表

createtableLLT_PVSHIELDRECORD

(

  id             CHAR(32)notnull,

  yearmonth       NUMBER(6),

  psr_id         CHAR(32),

  datatime       DATE,

  p_originalvalueFLOAT,

  p_replacevalue FLOAT,

  v_originalvalueFLOAT,

  v_replacevalue FLOAT

);

-- Add comments to the columns

commentoncolumnLLT_PVSHIELDRECORD.id

  is'ID';

commentoncolumnLLT_PVSHIELDRECORD.yearmonth

  is'所属月份';

commentoncolumnLLT_PVSHIELDRECORD.psr_id

  is'设备ID';

commentoncolumnLLT_PVSHIELDRECORD.datatime

  is'时间';

commentoncolumnLLT_PVSHIELDRECORD.p_originalvalue

  is'有功功率原始值';

commentoncolumnLLT_PVSHIELDRECORD.p_replacevalue

  is'有功功率替换值';

commentoncolumnLLT_PVSHIELDRECORD.v_originalvalue

  is'电压原始值';

commentoncolumnLLT_PVSHIELDRECORD.v_replacevalue

  is'电压替换值';

  altertableLLT_PVSHIELDRECORD

  addconstraintXPK_LLT_PVSHIELDRECORD primarykey(ID);