mysql - database creation field, what is the difference between default value empty and empty string 110

mysql database, navicat tool. Prerequisite, this field is set to NOT NULL, so the default value cannot be set ...

From [MySQLdiscussion group] 2017-05-18 10:55:59 0  1  1146

mysql-configuration - MySQL error, automatically hangs from time to time and cannot be started

mysql hangs up from time to time and cannot be started. What is the reason? my.cnf configuration: [client]port...

From [MySQLdiscussion group] 2017-05-18 10:55:52 0  6  739

How will the subsequent results of mysql order by subquery also be displayed in the result set?

How can the subsequent results of mysql order by subquery also be displayed in the result set? My mysql statem...

From [MySQLdiscussion group] 2017-05-18 10:55:42 0  1  636

Mysql startup error under centos

MySQL Daemon failed to start. This error is reported when starting mysql under centos. How to solve it?

From [MySQLdiscussion group] 2017-05-18 10:55:39 0  1  776

python - pymysql reports error 1146 The xls table failed to import into the database. I don't know where the problem lies.

Python 4.3.0 defines a class to operate the local database, and then defines two functions to import the corre...

From [MySQLdiscussion group] 2017-05-18 10:55:11 0  1  1205

mysql optimization - how to prevent full table updates in mysql

MySQL has a safe mode, but sometimes in business, you need to update multiple rows of records, but you want to...

From [MySQLdiscussion group] 2017-05-18 10:55:07 0  1  921

mysql - Why does the database need a lock mechanism?

Why does the database need a lock mechanism? Can you give a detailed example using code? Thank you!

From [MySQLdiscussion group] 2017-05-18 10:54:59 0  3  725

Mysql master-slave replication REPLICATE_DO_DB parameter rolls back to the initial settings every time after the slave server reboots

I built mysql master-slave replication on Microsoft Cloud and used bitnami with replication. My.cnf configurat...

From [MySQLdiscussion group] 2017-05-18 10:54:55 0  3  860

Reasons for Chinese garbled characters in MySQL database

This is the statement for creating a table in my database. This is the garbled picture of my database query. W...

From [MySQLdiscussion group] 2017-05-18 10:54:52 0  7  830

Can MySQL set a validity period for the value of a certain field?

I want to set a validity period of 10 minutes for the value of a certain field. After 10 minutes, it becomes N...

From [MySQLdiscussion group] 2017-05-18 10:54:45 0  4  1327

mysql - Since innodb has gap locks at the RR isolation level, why do two transactions still produce deadlocks due to different locking orders? ?

Deadlock is caused by multiple transactions competing for the same resource. Whether it is two SQL statements ...

From [MySQLdiscussion group] 2017-05-18 10:54:38 0  1  726

Mysql one-to-many How to perform multi-condition and multiple statistics on the slave table

Main table user table id name phone (associated field) slave table call record table id phone (associated fiel...

From [MySQLdiscussion group] 2017-05-18 10:54:32 0  3  827

mysql - Database design (scheme design), should NULL be avoided as much as possible?

I learned the actual phenomenon: NULL has unclear semantics and is not easy to optimize when querying. If it r...

From [MySQLdiscussion group] 2017-05-18 10:54:25 0  2  724

After installing mysql, the user name root is displayed when it is completed. When viewing the version on the terminal, it is not root. How can I solve this problem?

Terminal $ mysql -v ERROR 1045 (28000): Access denied for user 'zhangrui'@'localhost' (using password: NO) How...

From [MySQLdiscussion group] 2017-05-18 10:54:07 0  2  728

Database design - MySQL database integration of two systems

1. There are currently systems A and B, and B is the upgraded system of A; 2. The structure of most database t...

From [MySQLdiscussion group] 2017-05-18 10:54:00 0  3  827