SQL Server：在条件需要更多时间的情况下

Question

我有以下SQL查询需要更多时间来运行，即执行相同查询时执行4分钟以上，静态“1”或“0”值需要的时间少得多，即少于3-4秒：

select 
    column1, column2 
from 
    tablename
where  
    bitColumn_1 = (case when @bitColumn_1_param is null 
                           then bitColumn_1 
                           else @bitColumn_1_param 
                   end)
    and bitColumn_2 = (case when @bitColumn_2_param is null 
                               then bitColumn_2 
                               else @bitColumn_2_param 
                       end)
    and bitColumn_3 = (case when @bitColumn_3_param is null 
                               then bitColumn_3 
                               else @bitColumn_3_param 
                       end)
    and bitColumn_4 = (case when @bitColumn_4_param is null 
                               then bitColumn_4 
                               else @bitColumn_4_param 
                       end)
    and bitColumn_5 = (case when @bitColumn_5_param is null 
                          then bitColumn_5 
                          else @bitColumn_5_param 
                       end)
    and bitColumn_6 = (case when @bitColumn_6_param is null 
                               then bitColumn_6 
                               else @bitColumn_6_param 
                       end)
    and bitColumn_7 = (case when @bitColumn_7_param is null 
                               then bitColumn_7 
                               else @bitColumn_7_param 
                       end)

任何改进查询的帮助都会有所帮助！

提前致谢

Answer 1

您可以尝试下面的查询，这可能会帮助您

 select column1,column2 from tablename
 where bitColumn_1 = ISNULL(@bitColumn_1_param,bitColumn_1)
 AND bitColumn_2 =ISNULL(@bitColumn_2_param,bitColumn_2) 
 AND bitColumn_3 =ISNULL(@bitColumn_3_param,bitColumn_3) 
 AND bitColumn_4 =ISNULL(@bitColumn_4_param,bitColumn_4) 
 AND bitColumn_5 =ISNULL(@bitColumn_5_param,bitColumn_5)
 AND bitColumn_6 =ISNULL(@bitColumn_6_param,bitColumn_6) 
 AND bitColumn_7 =ISNULL(@bitColumn_1_param,bitColumn_7) 

Answer 2

create table #test
(bitcolumn1 nchar(10),
 bitcolumn2 nchar(10),
 bitcolumn3 nchar(10),
 bitcolumn4 nchar(10),
 bitcolumn5 nchar(10),
 bitcolumn6 nchar(10),
 bitcolumn7 nchar(10)
 )


 insert #test
 values
 ('x1',null,'x3','x4',null,'x6','x7')

 declare 
 @bitcolumn1 nchar(10)=null,
 @bitcolumn2 nchar(10)='z2',
 @bitcolumn3 nchar(10)='z3',
 @bitcolumn4 nchar(10)=null,
 @bitcolumn5 nchar(10)='z5',
 @bitcolumn6 nchar(10)='z6',
 @bitcolumn7 nchar(10)='z7'

 select  * from #test
 where bitcolumn1 =  coalesce(bitcolumn1,@bitcolumn1) and
       bitcolumn2=  coalesce(bitcolumn2,@bitcolumn2) and
       bitcolumn3 = coalesce(bitcolumn3,@bitcolumn3) and
       bitcolumn4 = coalesce(bitcolumn4,@bitcolumn4) and
       bitcolumn5 =  coalesce(bitcolumn5,@bitcolumn5) and
       bitcolumn6 =  coalesce(bitcolumn6,@bitcolumn6) and
       bitcolumn7 =  coalesce(bitcolumn7,@bitcolumn7)