如何优化嵌套条件SQL Server查询2008R2

Question

if {condition1} = '0'
begin
    if  {condition2} = 'Yes'
        Begin
            Set @SQLQuery = @SQLQuery + ' AND  '
        end
    else 
        begin
            Set @SQLQuery = @SQLQuery + ' AND  '
        end
end

Answer 1

正如@Pranav在评论中所述，您可以执行以下操作：

if {condition1} = '0'
  Set @SQLQuery = @SQLQuery + ' AND ' +
                  CASE WHEN {condition2} = 'Yes' THEN <whatever cond2=Yes>
                       ELSE <whatever cond2<>Yes> END

Answer 2

希望这有帮助，只需在运行此

之前为@SQLQuery分配任何或空值

SELECT @SQLQuery+ = CASE WHEN CONDITION1='0' AND CONDITION2='Yes' THEN
' AND '
WHEN CONDITION1='0' THEN
' AND '
END