mysql知识点

-- 更新空列 --
update middle_lte_resident_user set max_user=null;

--  删除空行--
DELETE FROM middle_lte_resident_user WHERE time_name IS NULL;

-- 删除临时表 --
drop table aa

-- 导入物理站址表 宏站 --
INSERT INTO result_alarm_info ( base_id, qux_county, xz_town_ship, cq_right ) SELECT
sade_id,
shud_county,
cell_city,
chanq_name 
FROM
souce_hongzhan_name;

-- 诺基亚 告警时间 关联lte表 --
UPDATE result_alarm_info a
LEFT JOIN middle_lte_config_info b ON a.base_id = b.base_id
SET a.alarm_time = b.type_time

-- 查询前几位 --
select SUBSTRING(z_name,30,6)from source_alarm_nokia

SELECT 
base_id
FROM  middle_lte_config_info 
GROUP BY base_id
ORDER BY base_id

DELETE FROM result_alarm_info
WHERE  alarm_type = 'Quality Of Service'