HELP 命令
句法
MariaDB [(none)]> HELP search_string
描述
The HELP
command can be used in any MariaDB / MySQL clients,
like the mysql command line client, to get basic help for MySQL syntax and a
short description for most commands and functions.
If you provide an argument to the help command, the mysql client uses it as a search string to access server-side help. The proper operation of this command requires that the help tables in the mysql database be initialized with help topic information.
If there is no match for the search string, the search fails:
MariaDB [(none)]> HELP something Nothing found Please try to run 'help contents' for a list of all accessible topics
Use help contents to see a list of the help categories:
MariaDB [(none)]> HELP contents You asked for help about help category: "Contents" For more information, type 'help <item>', where <item> is one of the following categories: Account Management Administration Compound Statements Data Definition Data Manipulation Data Types Functions Functions and Modifiers for Use with GROUP BY Geographic Features Language Structure Plugins Table Maintenance Transactions User-Defined Functions Utility
If the search string matches multiple items, mysql shows a list of matching topics:
MariaDB [(none)]> help create Many help items for your request exist. To make a more specific request, please type 'help <item>', where <item> is one of the following topics: CREATE DATABASE CREATE EVENT CREATE FUNCTION CREATE FUNCTION UDF CREATE INDEX CREATE PROCEDURE CREATE SERVER CREATE TABLE CREATE TABLESPACE CREATE TRIGGER CREATE USER CREATE VIEW SHOW SHOW CREATE DATABASE SHOW CREATE EVENT SHOW CREATE FUNCTION SHOW CREATE PROCEDURE SHOW CREATE TABLE SPATIAL
Use a topic as the search string to see the help entry for that topic.
The help is provided with the MariaDB server and the help tables are populated
with the mysql_install_db
or the
fill_help_table.sql
scripts.