SQL server添加where子句不会影响结果

Question

我有以下查询

  select count(person),  from [table]
  where (date > '2015-01-01')
  group by person

此查询返回100作为结果，我需要知道如何使用LIKE在where子句中添加另一个条件并获得相同的结果（100）

  select count(person),  from [table]
  where (date > '2015-01-01' and name LIKE '%?%')
  group by person

如果添加了名称列事件，它应该对最终结果

没有影响

Answer 1

这是两种方法，但这是什么意思？

select count(person),  from [table]
where (date > '2015-01-01' and (name LIKE '%' or name is null))
group by person

或者：

select count(person),  from [table]
where (date > '2015-01-01' and (name LIKE '%sometext%' or 1 = 1))
group by person

Answer 2

您是否了解TOP clause？

select TOP 100 count(person) As PersonCount, Person
from [table]
where (date > '2015-01-01' and name LIKE '%?%')
group by person

Answer 3

试试这个：

select top 100 count(person),  from [table]
where (date > '2015-01-01' and name LIKE '%?%')
group by person

假设name包含?的结果超过100个，则结果会有所不同。