MySQL 基本语句记录

2021-01-13 14:20:29 浏览数 (1)

-- 查询 select column1,column2 from table

select column1,column2 from table where id = 1

-- 查询:去掉某字段重复项,结果为这个字段

SELECT DISTINCT (column) FROM table

-- 查询:去掉某字段重复项,结果可指定字段

select * from tablegroup by column

-- 内连接查询

select * from table1,table2 where table1.id = table2.id select * from table1 inner join table2 on table1.id = table2.id -- 左右连接查询 select * from table1 right join table2 on table1.id = table2.id select * from table1 left join table2 on table1.id = table2.id -- 全连接查询 select * from table1 right join table2 on table1.id = table2.id union select * from table1 left join table2 on table1.id = table2.id

-- 限制查询

select * from table1 limit 0,5

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-- 插入 insert into table (column1,column2) values (column_value1,column_value2)

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-- 更新 update table set column1 = 'column_value1',column2 = 'column_value2' where id = 1 ------------------------------------------------------------------------------------------------------------ -- 删除 delete from table where id = 1

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-- 排序 select * from table1 order by id select * from table2 order by id desc ------------------------------------------------------------------------------------------------------------ -- 统计 select max(id) from table1 select min(id) from table1 select sum(id) from table1 select avg(id) from table1 select count(id) from table1 where pid = 1 select count(id) from table1 where table1.pid = table2.pid group by table1.pid

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-- 使用select结果语句创建新表 CREATE TABLE new_table (SELECT * FROM old_table);

CREATE TABLE box_total(

select pathway,pathwayName

FROM ( select pathway,pathwayName from box_human UNION select pathway,pathwayName from box_monkey UNION SELECT pathway,pathwayName from box_mouse UNION SELECT pathway,pathwayName from box_ox UNION SELECT pathway,pathwayName from box_pig UNION SELECT pathway,pathwayName from box_rat order by pathway ) as TB )

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