mysql select multiple ids

What should I do if a MySQL field contains multiple IDs? The following describes how to process a single MySQL field containing multiple IDs. The following is a complete example of a MySQL field containing multiple IDs. 1. Create a table create 

Batch update names separated by commas (,) (multiple IDs separated by commas (,) in a department are converted into names separated by commas (,) (mysql) and comma (,) mysqlUpdate dept B, (select group_concat (t. deptId), group_concat (d. deptName

Update Dept B, (select Group_concat (T.deptid), Group_concat (d.deptname separator '/') as Dname, T.id, t.deptname from (sel ECT Substring_index (Substring_index (A.deptid, ', ', b.help_topic_id+1), ', ', -1) as DeptID, a.ID, A.deptnameFrom(select D.

18.2.1 MySQL server has gone away errors related to Lost connection to server during query. The most common cause of the MySQL server has gone away error is that the server times out and closes the connection. By default, if nothing happens, the

In mysql, if we want to query records, we will use the select statement. Next I will summarize the various operations on the mysql select statement. If you need to learn more, please do not go to the reference. The most common database operations

Common commands for MySQL database operations and Common commands for mysql Common commands for MySQL database operationsDOS Connection database1. Install MySQL to configure the environment2. Run the cmd command. net start mysql3. Find the root

In order to better optimize MySQL in high concurrency, it is necessary to understand the locking table mechanism when MySQL query is updated.I. OverviewMySQL has three levels of Lock: page level, table level, row level.MyISAM and MemoryStorageThe

MySQL performance tuning and Architecture Design-Chapter 1 Data splitting of scalability design and mysql Optimization Chapter 1 Data splitting for scalable design Preface The expansion implemented through the MySQL Replication function is always

DirectoryPrinciple 1Master-Slave Synchronization configuration 2Master server Synchronization User Authorization 2Configuring MY.CNF files for MySQL master server 3Standby configuration: 4Common commands: 5Dual master Configuration my.cnf

This article is a basic tutorial on Mysql. it teaches you how to easily learn Mysql commands and master Mysql commands. For more information, see I. INTRODUCTION to MySQL concepts MySQL is a Relational Database Management System. this so-called