How to view help for mysql: View customized operation statements by executing the [? data definition] command. You can also view the data types supported by the database by executing the [?data types] command.
The details are as follows:
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MySQL database is helpful Command, you can use the command to view the categories available for query. The operation command is:
？ contents
To view the MySQL custom operation statement, you can use the command:
? data definition
If you want to check which data types are supported by the MySQL database, you can use the command:
? data types
View the description of the data type varchar, You can use the command:
? varchar
The show command is often seen in MySQL statements, such as show databases, show tables, etc. So what are the show commands? , you can use the command:
？ show
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