Basic concepts and Common commands of MySQL

1 MySQL Introduction
Reference
Mysql was developed by more than 1985 Swedish boys. Later, they established Mysql AB. At that time, they developed mysql to provide data warehouse services for retailers, this is why mysql is good at querying rather than processing transactions. Therefore, they designed a method to store data using the index sequence, that is, the ISAM storage engine algorithm, and later developed into the MyISAM storage engine. Mysql features high performance, high reliability, and ease of use. It is mainly suitable for web site systems, log recording systems, data warehouse systems, and embedded systems.

2. Mysql architecture composition
Reference
Physical Components of mysql: log files, data files, Replication-related files, and other files

Reference
System Architecture of mysql server: SQL Layer and Storage Engine Layer

Reference
Mysql built-in tools
# Run the ping command to check whether the server provides sufficient services.
Mysqladmin-uroot-proot-h localhost ping

# Status Command to view the status values of the current msyql server
Mysqladmin-uroot-proot-h localhost status

# Processlist command to obtain information about the current database connection thread
Mysqladmin-uroot-proot-h localhost processlist

3. MySQL plug-in storage engine Introduction
Reference
Each table of the MyISAM engine is stored as three physical files named after the table name: tableName. frm, tableName. MYD, tableName. MYI
Three indexes are supported: B-Tree, R-Tree, and Full-text (B-Tree, which solves the like Query inefficiency problem)

Reference
Features of the InnoDB Storage engine: Transaction Security, multi-version Data Reading, and foreign key support