Question

在我的一个表字段中，我包含年龄范围。它们将采用

之类的格式

27-51,18-28,10-17
37-55,60-70
1-5,11-16,30-32,60-90
etc

我正在尝试建立一个SELECT语句，我可以在其中搜索给定的年龄是否在任何范围内...类似

SELECT * from table where age IN (1-5,11-16,30-32,60-90)

但是它将在给定范围内搜索

如果我只有一个范围，则可以使用...

WHERE age 
BETWEEN
SUBSTRING_INDEX(personsAge,"-",1) + 0 AND
SUBSTRING_INDEX(personsAge,"-",-1) + 0

但是如果我有多个范围怎么办？

Answer 1

这是我在上面发表评论的答案。我假设您可以创建一个函数：

注意：这是针对Sql Anywhere的。请调整MySql的语法（尤其是在切换参数的locate函数）。该代码尚未准备就绪，因此我省略了一些有效性检查。我假设该列中的值均格式正确。

注意2 ：这是有人向您转储糟糕的数据库设计并要求您解决问题的情况之一。请避免需要这种解决方案。

功能：

CREATE FUNCTION "DBA"."is_in_range"(age_range varchar(255), age int)
returns int
begin 
  declare pos int;
  declare pos2 int;
  declare strPart varchar(50);
  declare strFrom varchar(10);
  declare strTo varchar(10);
  declare iFrom int;
  declare iTo int;

  while 1 = 1 loop
    set pos = locate(age_range, ',');
    if pos = 0 then
      -- no comma found in the rest of the column value -> just take the whole string
      set strPart = age_range;
    else 
      -- take part of the sting until next comma
      set strPart = substr(age_range, 1, pos - 1);
    end if;
    -- we are parsing the min-max part and do some casting to compare with an int
    set pos2 = locate(strPart, '-');
    set strFrom = substr(strPart, 1, pos2 - 1);
    set strTo = substr(strPart, pos2 + 1);
    set iFrom = cast(strFrom as int);
    set iTo = cast(strTo as int);

    if age between iFrom and iTo then
      return 1;
    end if;
    -- if at end of age_range then quit
    if pos = 0 then
      return 0;
    end if;
    -- get the next part of the string after the comma
    set age_range = substr(age_range, pos + 1);
    set pos = locate(age_range, ',', pos);
  end loop;

  return 0;
end;

测试数据：

create local temporary table #tmpRanges (ident int, age_range varchar(255));
insert into #tmpRanges (ident, age_range) values (1, '27-51,18-28,10-17');
insert into #tmpRanges (ident, age_range) values (2, '37-55,60-70');
insert into #tmpRanges (ident, age_range) values (3, '1-5,11-16,30-32,60-90');
insert into #tmpRanges (ident, age_range) values (4, '1-50');

致电：

select * from #tmpRanges where is_in_range(age_range, 51) = 1;
select * from #tmpRanges where is_in_range(age_range, 10) = 1;
select * from #tmpRanges where is_in_range(age_range, 9) = 1;
etc...

mysql搜索逗号列表的数字范围

1 个答案: