筛选匹配字符串：
select * from direction_en where “from” like ‘% S8 %’
统计某一列数据的频率：
select author_id,count(*) cnt from
(select * from direction_en where “from” like ‘% S8 %’) as newtable
group by author_id
数据操作
更新（字段名词要引用）：
update
direction_en
set “Building” =’S8’
where “from” like ‘% S8 %’
group by 关键字
select “Building”,count (“Building”)
from direction_en
group by “Building”
order by count
group by 和distinct 同时使用
select “Building”,count(distinct “author_id”)
from direction_en
group by “Building”
order by “count”
清空数据表
delect from table name
插入数据：
insert tablename (field1, field2,field3, field4) values(value1, value2,value3, value4)