T-SQL-一行上有多个逗号分隔的值

Question

I have table (T-SQL) with 2 attributes - Code and Range.

Code                 Range
-------------------- ----------
5000_RANGE           5001..5003
5001                 NULL
5002                 NULL
5003                 NULL
5802                 NULL
5802_RANGE           5802..5804
5803                 NULL
5804                 NULL
6401                 NULL

I'm trying to write a simple query to get the Code values with '_RANGE' postfix and the Code values (separated by commas) specified by Range attribute on a single line.

Code                 Range
-------------------- --------------
5000_RANGE           5001,5002,5003
5802_RANGE           5802,5803,5804

What is the best solution? Maybe somehow by using XML Path()?

Answer 1

You can get the list using a self-join:

select range.code, c.code
from (select code, range
      from t
      where code like '%RANGE'
     ) range left outer join
     (select t.*
      from t
      where code not like '%RANGE'
     ) c
     on c.code between left(range.range, 4) and right(range.range, 4)

Getting them into a comma separate list depends on the database. Here is the method in MySQL:

select range.code, group_concat(c.code)
from (select code, range
      from t
      where code like '%RANGE'
     ) range left outer join
     (select t.*
      from t
      where code not like '%RANGE'
     ) c
     on c.code between left(range.range, 4) and right(range.range, 4)
group by range.code

Answer 2

Try this. Create a function like below:

ALTER FUNCTION GetRangeText
(
    @Value VARCHAR(50)
) RETURNS VARCHAR(100)
AS
BEGIN
    DECLARE @Start AS INT
    DECLARE @End AS INT
    DECLARE @RangeText AS VARCHAR(200)
    SET @RangeText = ''

    SET @Start = CAST(SUBSTRING(@Value, 0, CHARINDEX('...', @Value)) AS INT)
    SET @End = CAST(SUBSTRING(@Value, CHARINDEX('...', @Value) + 3, LEN(@Value)) AS INT)

    WHILE @Start <= @End
    BEGIN       
        SET @RangeText = @RangeText + CAST(@Start AS VARCHAR(100)) + ','

        SET @Start = @Start + 1
    END

    RETURN @RangeText
END

Consume the function in the SELECT query like below

SELECT Code, dbo.GetRangeText(Range) FROM Table1 WHERE Code LIKE '%_RANGE'

This will give the excepted output.

Answer 3

You didn't specify which DBMS you are using. If you are using MySQL you could use a query like this:

SELECT
  Code,
  GROUP_CONCAT(SUBSTRING_INDEX(rng, '..', 1)+numbers.digit) ranges
FROM
  (SELECT 0 digit UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL
   SELECT 4 UNION ALL SELECT 4 UNION ALL SELECT 5) numbers
  INNER JOIN
  codes
  ON SUBSTRING_INDEX(rng, '..', -1)-SUBSTRING_INDEX(rng, '..', 1)>=numbers.digit
WHERE
  rng like '%..%'
GROUP BY
  Code

Which gives exatly the result you need.

Please see fiddle here . It can be improved to support larger ranges.

Answer 4

Something like

SELECT Code, Range FROM code_table WHERE Code LIKE "%_RANGE"

Not sure about presenting the range how you like.