将nvarchar转换为int错误

Question

我有这个查询，我不能完全解决我得到的错误。

将nvarchar值“ 1.5”转换为数据类型int时，转换失败。

这是由于pvlaue在一种情况下拉出“ 1.5”字符串并将其隐式转换为int所致。 我试图通过将其转换为浮点数来纠正此问题，但这似乎对我不起作用。 在这方面的任何帮助将非常有帮助。

我正在SQL Server 2012 Management Studio上运行它。

BEGIN DECLARE @Item NVARCHAR(100)
SET @Item = 'Water'

SELECT 
    d.DESCRIPTION, d.ITEM_CODE,  
    el.ENUM_LABEL as Building_Block, 
    CAST(itpC.pvalue AS DECIMAL(22, 3)), ffi.where_used,
    d.STATUS_IND
FROM 
    FSITEM d
LEFT JOIN 
    FSITEMTECHPARAM itp ON d.ITEM_CODE = itp.ITEM_CODE 
                        AND itp.PARAM_CODE = 'BUILDING_BLOCK'
LEFT JOIN 
    FSVALIDENUMVALCF ev ON CAST(coalesce(itp.PVALUE, 0) as float) = CAST(ev.ENUM_VALUE AS FLOAT)
                        AND ev.ENUM_CODE = 'C_BUILDING_BLOCK_TYP'
LEFT JOIN 
    FSVALIDENUMLABELCF el ON ev.ENUM_CODE = el.ENUM_CODE 
                          AND ev.ENUM_ORDER = el.ENUM_ORDER 
                          AND el.LANGUAGE_CODE = 'EN-US'
LEFT JOIN
    (SELECT 
         item_Code, max(CAST(pvalue AS FLOAT)) as pvalue
     FROM 
         FSITEMTECHPARAM
     JOIN
         KC_SITE_COST_MAP ON FSITEMTECHPARAM.PARAM_CODE = 'COST_'+KC_SITE_COST_MAP.COST_CODE
     GROUP BY 
         ITEM_CODE

     UNION

     SELECT
         ITEM_CODE, CAST(pvalue AS FLOAT) as pvalue
     FROM  
         FSFORMULA
     JOIN
         FSFORMULATECHPARAM ON FSFORMULA.FORMULA_ID = FSFORMULATECHPARAM.FORMULA_ID
                            AND PARAM_CODE = 'COST_TOTAL_BASE'
     WHERE 
         FSFORMULA.FORMULA_ID IN (SELECT FORMULA_ID FROM FSITEM)) itpC ON D.item_code = itpC.item_code
LEFT JOIN 
    (SELECT
         ffi.item_code, COUNT(distinct ffi.formula_id) where_used 
     FROM
         fsformulaingred ffi 
     JOIN
         fsformula ff ON ffi.formula_id = ff.formula_id 
     WHERE
         ff.status_ind = 500 AND ff.logical_delete = 0  
     GROUP BY
         ffi.item_code) ffi ON D.item_code = ffi.item_code 
WHERE 
    d.LOGICAL_DELETE = 0 
    AND d.COMPONENT_IND <> 2 
    AND d.Status_IND < 600
    AND (((CAST(ev.ENUM_VALUE as FLOAT) = 3 or CAST(ev.ENUM_VALUE as FLOAT) = 2)  
    AND d.Status_Ind < 600) OR
       CAST(ev.ENUM_VALUE as FLOAT) = 1 or CAST(ev.ENUM_VALUE as FLOAT) = '0') 
    AND (d.Description Like @Item + '%')
    --Or d.Description Like replace(@Item, '!', '%'))
ORDER BY 
    CAST(coalesce(ev.enum_value,0) as FLOAT) DESC, status_ind DESC, d.Item_Code
END

Answer 1

是将coalesce转换为int ，因此从coalesce转换结果为时已晚。

无论如何评估表达式，表达式的结果必须具有相同的类型。 表达coalesce(itp.PVALUE, 0)将成为类型的int无论的值是否itp.PVALUE或者值0时，由于类型0是int 。

如果投射的0至float ，表达式的类型将是float ，所以使用coalesce(itp.PVALUE, cast(0 as float))