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SQL how to select date from 1 - many

开发者 https://www.devze.com 2023-03-05 07:27 出处:网络
In SQL 2005 stored proc I need to run a query that contains a 1-M. I need to return only 1 of the Many table the one with the earliest date.

In SQL 2005 stored proc I need to run a query that contains a 1-M. I need to return only 1 of the Many table the one with the earliest date.

I have looked at In SQL how do I write a query to return 1 record from a 1 to many relationship?

and SQL conundrum, how to select latest date for part, but only 1 row per part (unique)

But I am not sure what's the best solution in my case as I am also doing a Insert Into temp table and using dynamic sorting and paging.

Here is my SQL. What I want is to return many rows of Foo, but only the earliest b.CreatedDate between the start and end data paramaters I pass in where there is normally about 5 rows in Bar for each Foo.

DECLARE      @StartDate datetime 
 DECLARE     @EndDate datetime 

INSERT INTO @Results
          SELECT distinct
                f.Name,
                 f.Price
                b.CreatedDate ,
                // loads more columns removed for brevity   
          FROM
                foo f
            join bar b on f.Id = b.fooId
               // loads more table removed 开发者_如何转开发for brevity 
          WHERE
                (@x is null OR f.Id = @x)
            AND (@Deal is null OR f.IsDeal = @Deal)
            AND (@StartDate is null OR sd.SailingDate >= @StartDate)
            AND (@EndDate is null OR sd.SailingDate <= @EndDate)
                  // loads more filters removed for brevity 

        declare @firstResult int, @lastResult int
        set @firstResult = ((@PageNumber-1) * @ItemsPerPage) + 1;
        set @lastResult = @firstResult + @ItemsPerPage;
        select @TotalResults = count(1) from @Results;

        WITH ResultItems AS
        (
            SELECT *, ROW_NUMBER() OVER (
                ORDER BY
                CASE    WHEN @SortBy = 'priceLow' THEN Price END ASC,
                CASE    WHEN @SortBy = 'Soonest' THEN CreatedDate END ASC,
                CASE    WHEN @SortBy = 'priceHigh' THEN Price END DESC
            ) As  RowNumber
            FROM @Results r
        )
        SELECT * from ResultItems
        WHERE RowNumber >= @firstResult AND RowNumber < @lastResult
        ORDER BY
        CASE
            WHEN @SortBy = 'priceHigh' THEN (RANK() OVER (ORDER BY Price desc))
            WHEN @SortBy = 'priceLow' THEN (RANK() OVER (ORDER BY Price))
            WHEN @SortBy = 'Soonest' THEN (RANK() OVER (ORDER BY CreatedDate )) 
        END 

This query as is will return multiple 'b.CreatedDate' instead of just the earliest one between my Filters

Update So I want to See If my source data is:

Foo
___
1  , Hello
2  , There

Boo
___
1, 1,   2011-2-4
2, 1,   2011-3-6
3, 1,   2012-12-21
4, 2,   2012-11-2

The result would be

1, Hello,2011-2-4
2, There,  2012-11-2


I think I just got it working by adding a CTE to the top of my query

;with cteMinDate as (
    select FooId, min(CreatedDate) As CreatedDate
    from Bar            WHERE
          (@StartDate is null OR CreatedDate>= @StartDate)
          AND (@EndDate is null OR CreatedDate<= @EndDate)
        group by FooId
)

Same as shown here SQL conundrum, how to select latest date for part, but only 1 row per part (unique). Doing this allows me to remove the date query part from my main query and only do it once in the CTE

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