1>自定义比较函数,targetVal的值为字符串,例如:“>=90”,"2~8"等范围格式,dataVal值为字符串。
create or replace function compare1(targetVal in varchar2,
dataVal in varchar2) return integer is
v_Result integer;
dataVal_int number;
targetVal_int number;
v_targetVal varchar2(200);
v_dataVal varchar2(200);
v_flag boolean;
v_index integer;
begin
v_flag := true;
v_targetVal := replace(targetVal, ' ');
v_dataVal := replace(dataVal, ' ');
dataVal_int := to_number(v_dataVal);
if instr(v_targetVal, '>=') > 0 then
v_targetVal := replace(v_targetVal, '>=');
targetVal_int := to_number(v_targetVal);
v_flag := dataVal_int >= targetVal_int;
elsif instr(v_targetVal, '>') > 0 then
v_targetVal := replace(v_targetVal, '>');
targetVal_int := to_number(v_targetVal);
v_flag := dataVal_int > targetVal_int;
elsif instr(v_targetVal, '<=') > 0 then
v_targetVal := replace(v_targetVal, '<=');
targetVal_int := to_number(v_targetVal);
v_flag := dataVal_int <= targetVal_int;
elsif instr(v_targetVal, '<') > 0 then
v_targetVal := replace(v_targetVal, '<');
targetVal_int := to_number(v_targetVal);
v_flag := dataVal_int < targetVal_int;
elsif instr(v_targetVal, '~') > 0 then
v_index := instr(v_targetVal, '~');
v_flag := dataVal_int <= to_number(substr(v_targetVal, v_index + 1)) and
dataVal_int >=
to_number(substr(v_targetVal, 1, v_index - 1));
elsif instr(v_targetVal, '=') > 0 then
v_targetVal := replace(v_targetVal, '=');
targetVal_int := to_number(v_targetVal);
v_flag := dataVal_int = targetVal_int;
elsif instr(v_targetVal, '=') = 0 then
targetVal_int := to_number(v_targetVal);
v_flag := dataVal_int = targetVal_int;
end if;
if v_flag then
v_Result := 1;
else
v_Result := 0;
end if;
return(v_Result);
exception
when others then
return 1;
end compare1;
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