Mysql的常见错误及常用操作（根据身份证、生日获取年龄等）
以下是mysql的一些常见操作及问题处理，后续会陆续追加
【Mysql】如何查询数据库中存在某一个字段的所有表？
数据库里的表很多，一时之间忘记了要找的表，只记得其中的某些字段，可以用下面的sql来查询在这个数据库中，存在这个字段的所有表，是不是就缩小查找范围了呢？
SELECT DISTINCT TABLE_NAME FROM information_schema.COLUMNS WHERE COLUMN_NAME = 'sex' AND TABLE_SCHEMA='dbName' AND TABLE_NAME NOT LIKE 'sex%';
mysql创建函数错误，
set global log_bin_trust_function_creators=TRUE;
mysq根据生日获取年龄:
SELECT birthday , IFNULL(TIMESTAMPDIFF(YEAR, birthday, CURDATE()),0) AS age FROM table(你的表名称)
SELECT TIMESTAMPDIFF(YEAR, birthday, CURDATE()) age ,birthday FROM table(你的表名称)
mysq根据身份证修改生日:
update
table(你的表名称) set birth_date = DATE_FORMAT(SUBSTR(id_card,7,8),'%Y-%m-%d')
where LENGTH(id_card)=18 and id_card regexp '^[1-9][[:digit:]]{7}((0[[:digit:]])|(1[0-2]))(([0|1|2][[:digit:]])|3[0-1])[[:digit:]]{3}$|^[1-9][[:digit:]]{5}[1-9][[:digit:]]{3}((0[[:digit:]])|(1[0-2]))(([0|1|2][[:digit:]])|3[0-1])[[:digit:]]{3}([0-9]|X)$'
--------------数据库表信息查看
select TABLE_SCHEMA '数据库名称',TABLE_NAME '表名称', COLUMN_NAME '字段名称',COLUMN_TYPE '字段类型',EXTRA AS 'PK主键',is_nullable '是否可为空',COLUMN_COMMENT '字段说明' from information_schema.columns where TABLE_SCHEMA='数据库名称';
SELECT table_name, table_comment
FROM information_schema.tables
WHERE table_schema = '数据库名称'
-- 修改字段属性，以0001的形式进行展示
alter table 表名称 MODIFY COLUMN 字段名称 int(4) zerofill not null
--mysql的复杂性策略设置
关闭密码复杂性策略
SET global validate_password_policy = 0;
设置密码复杂性要求密码最低长度为1
SET global validate_password_length = 1;
查看密码复杂性策略
SELECT @@validate_password_policy;
查看密码复杂性要求密码最低长度大小
SELECT @@validate_password_length;
#尝试修改密码
#自己选方式都可
alter user 'root'@'localhost' identified by '123456';
set password for 'root'@'localhost' = password('123456');
set password for 'root'@'%' = password('123456');
#刷新配置
flush privileges;
设置mysql登录失败、登录超时等
INSTALL PLUGIN connection_control SONAME 'connection_control.so';
show variables like 'connection_control%';
SHOW GLOBAL VARIABLES LIKE '%timeout%';
set GLOBAL wait_timeout=300;
set GLOBAL interactive_timeout=300;
install plugin CONNECTION_CONTROL soname 'connection_control.so';
install plugin CONNECTION_CONTROL_FAILED_LOGIN_ATTEMPTS soname 'connection_control.dll';
show variables like '%plugin%';
install plugin CONNECTION_CONTROL soname 'connection_control.dll';
INSTALL PLUGIN CONNECTION_CONTROL
SONAME 'connection_control.dll';
INSTALL PLUGIN CONNECTION_CONTROL_FAILED_LOGIN_ATTEMPTS
SONAME 'connection_control.dll';
mysql删除身份证重复的数据
delete ymf_person_base_info
from
ymf_person_base_info,
(
SELECT
min(id) id,
id_card
FROM
ymf_person_base_info
GROUP BY
id_card
HAVING
count(*) > 1
) t2
where ymf_person_base_info.id_card = t2.id_card
and ymf_person_base_info.id > t2.id
----mysql连接报错
Connections using insecure transport are prohibited while --require_secure_transport=ON
set global require_secure_transport=off
mysql查看数据的总数量
1.数据库查询总条数
use information_schema;
select sum(table_rows) from tables where TABLE_SCHEMA = 数据库名称;
2.mysql 查看数据库中所有表的记录数
use information_schema;
select table_name,table_rows from tables
where TABLE_SCHEMA = '数据库名称'
order by table_rows asc;