Clickhouse SQL查询技巧

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clickhouse 在关联不上的情况会返回0值，而不是MySQL返回Null

select *  from
   (select 1 as a union all
    select 2  as a union all
    select 3  as a union all
    select 0  as a union all
    select 0  as a) x
left join (
select 2  as b, ‘adc‘ as c union all
    select 3  as b, ‘adc‘ as c union all
    select 5  as b, ‘adc‘ as c union all
    select 0  as b, ‘adc‘ as c union all
    select 0  as b, ‘adc‘ as c
           ) y on x.a = y.b
-- where c= ‘‘
order by a

Clickhouse SQL查询技巧

标签：use   情况   order   nio   sql查询   null   sql   click   返回   

原文地址：https://www.cnblogs.com/malcolmwallace/p/14664134.html