How to view MySQL Help documentation efficiently

During theuse of mysq L, you may often encounter the following issues:

• Some operation syntax forgot, how to quickly find?
• How do I quickly know the range of values for a field type on the current version?
• What functions are supported in the current version? I hope there are examples to illustrate:
• Does the current version support a feature?

for the problems listed above, we might think of a way to find MySQL documents, which can be clearly found in official documents, but it takes a lot of time and effort.
so for these questions, the best solution is to use the MySQL installed after the help document, so that in case of problems can be easily and quickly query.  view Help by HierarchyView Catalog If you do not know what help can provide, you can use the "? Contents" command to display all the categories available for querying, as shown in the following example:

Mysql>? Contentsyou asked for help in the category: "Contents" For more information, type ' help <item> ', where <ITEM&G T is one of the followingcategories: account   Management   Administration   Compound Statements   Data Definition   Data Manipulation   data Types   Functions   Functions and Modifiers for use with GROUP by   Geographic Features   Help Metadata   Language Structure   Plugins   procedures   Storage Engines   Table Maintenance   Transactions   user-defined Functions   Utility

View Data Typesfor the categories listed, you can use the "?????????" method to make a further view of what the user is interested in, for example, to see what data types are supported by MySQL and to execute the "? Data tyeps" command:

Mysql>? Data typesyou asked for help on Help category: "Data Types" For more information, type ' help <item> ', where <it Em> is one of the followingtopics:   auto_increment   BIGINT   BINARY   BIT   blob   blob DATA TYPE   BOOLEAN   Char   char BYTE   DATE   DATETIME   DEC   DECIMAL   double   double PRECISION   ENUM   FLOAT   INT   INTEGER   longblob   longtext   mediumblob   mediumint   mediumtext   SET DATA TYPE   SMALLINT   TEXT   time   TIMESTAMP   tinyblob   TINYINT   tinytext   VARBINARY   VARCHAR   Year DATA TYPE

all the data types supported by this version are listed above, and if you want to know the specific description of the int type, you can also use the above method to do a further review:

Mysql>? Intname: ' INT ' description:int[(M)] [UNSIGNED] [zerofill]a normal-size Integer. The signed range is-2147483648 to 2147483647.The unsigned range are 0 to 4294967295.URL:HTTP://DEV.MYSQL.COM/DOC/REFMAN/5 .5/en/numeric-type-overview.html

View functions

Mysql>? Functionsyou asked for help in the category: "Functions" For more information, type ' help <item> ', where <item > is one of the followingcategories:   Bit Functions   Comparison operators   Control flow Functions   Date and time Functions   encryption Functions   information Functions   Logical operators   Miscellaneous Functions   Numeric Functions   String Functions

then look at the corresponding function according to the listed directory, for example, see what date function

Mysql>? Date and time Functionsyou asked for help on Help category: "Date and Time Functions" For more information, type ' Help & Lt;item> ', where <item> is one of the followingtopics:   adddate   addtime   convert_tz   curdate   current_date   Current_time   current_timestamp   curtime   DATE FUNCTION   DATEDIFF   date_add   date_format   date_sub   Day   dayname   dayofmonth   DAYOFWEEK   dayofyear   EXTRACT   from_days   from_unixtime   Get_format   HOUR   last_day   localtime   localtimestamp   makedate   maketime   microsecond   MINUTE   MONTH   MONTHNAME   now   period_add   period_diff   QUARTER   SECOND   sec_to_time   str_to_date   subdate   Subtime   sysdate time   function   timediff   TIMESTAMP FUNCTION   timestampadd   Timestampdiff   time_format   time_to_sec   to_days   to_seconds   unix_timestamp   utc_date   Utc_time   Utc_timestamp   WEEK   WEEKDAY   weekofyear   year   Yearweek

Quick Check Helpin practical applications, you can use keywords for quick queries if you need to quickly review a grammar. For example, to know what the show command can see, use the following command:

Mysql>? ShowName: ' SHOW ' description:show have many forms that provide information about databases, tables,columns, or status Inform ation about the server. This section describesthose following:show authorsshow {BINARY | MASTER} logsshow BINLOG EVENTS [in ' Log_name '] [from POS] [LIMIT [offset,] row_count]show CHARACTER SET [Like_or_where]sho W COLLATION [Like_or_where]show [Full] COLUMNS from Tbl_name [from db_name] [like_or_where]show contributorsshow CREATE DA Tabase db_nameshow Create EVENT event_nameshow Create FUNCTION func_nameshow Create PROCEDURE proc_nameshow create TABLE t Bl_nameshow Create TRIGGER trigger_nameshow Create VIEW view_nameshow DATABASES [like_or_where]show ENGINE engine_name {S Tatus | Mutex}show [STORAGE] enginesshow ERRORS [LIMIT [offset,] row_count]show eventsshow function CODE func_nameshow function ST ATUs [like_or_where]show GRANTS for Usershow INDEX from Tbl_name [from Db_name]show MASTER statusshow OPEN TABLES [from DB _name] [Like_or_where]show pluginsshow PROCEDURE CODE proc_nameshow PROCEDURE STATUS [Like_or_where]show privilegesshow [Full] processlistshow profile [types] [ For QUERY n] [OFFSET n] [LIMIT n]show profilesshow SLAVE hostsshow SLAVE statusshow [GLOBAL | SESSION] Status [like_or_where]show TABLE status [from db_name] [like_or_where]show [Full] TABLES [from db_name] [like_or_ Where]show TRIGGERS [from db_name] [like_or_where]show [GLOBAL | SESSION] VARIABLES [like_or_where]show WARNINGS [LIMIT [offset,] row_count]like_or_where:like ' pattern ' | WHERE Exprif The syntax for a given SHOW statement includes a like ' pattern ' part, ' pattern ' was a string that can contain t He SQL "%" and "_" wildcard characters. The pattern is useful-restricting statementoutput to matching values. Several SHOW Statements also accept a WHERE clause that provides moreflexibility in specifying which rows to display. Seehttp://dev.mysql.com/doc/refman/5.5/en/extended-show.html.url:http://dev.mysql.com/doc/refman/5.5/en/show.html

view a function concat use

mysql> concatname: ' CONCAT ' Description:Syntax:CONCAT (str1,str2,...) Returns the string that results from concatenating the arguments. Mayhave one or more arguments. If all arguments be nonbinary strings, Theresult is a nonbinary string. If the arguments include any binarystrings, the result is a binary string. A numeric argument is convertedto its equivalent string form. This is a nonbinary string as of MySQL5.5.3. Before 5.5.3, it is a binary string; To-avoid that andproduce a nonbinary string, you can use the a explicit type cast, as Inthis example:select CONCAT (CAST (in T_col as CHAR), Char_col); CONCAT () returns null if any argument is null.        url:http://dev.mysql.com/doc/refman/5.5/en/string-functions.htmlexamples:mysql> SELECT CONCAT (' My ', ' S ', ' QL ');        ' MySQL ' mysql> SELECT CONCAT (' My ', NULL, ' QL ');        -Nullmysql> SELECT CONCAT (14.3); ' 14.3 ' 

For example, if you want to see the syntax for CREATE TABLE , you can use the following command:

Mysql>? Create TableName: ' Create TABLE ' Description:Syntax:CREATE [temporary] table [IF not EXISTS] tbl_name    (create_ Definition,...)    [Table_options]    [Partition_options] or:create [temporary] TABLE [IF not EXISTS] tbl_name    [(create_definition,...)]    [Table_options]    [Partition_options]    select_statementor:create [temporary] TABLE [IF not EXISTS] tbl_name    {like Old_tbl_name | (like Old_tbl_name)}    ......

One more example, like to see how to write the user grant syntax.

Mysql>? Grantname: ' GRANT ' Description:Syntax:GRANT    priv_type [(column_list)]      [, Priv_type [(column_list]]] ...    On [object_type] priv_level to    user_specification [, user_specification] ...    [REQUIRE {NONE | ssl_option [[and] ssl_option] ...}]    [With With_option ...] GRANT PROXY on User_specification    to User_specification [, user_specification] ...    [With GRANT option]object_type:    TABLE  | FUNCTION  | PROCEDURE ...      

Here is the View manual and official information of the address presented, the mantle is passed to you, don't forget to give a praise Oh ~

Common network resources http://dev.mysql.com/downloads/is the official MySQL website that can be downloaded to various versions of MySQL and related client development tools.http://dev.mysql.com/doc/provides an online handbook of the most authoritative MySQL databases and tools available today. http://bugs.mysql.com/can see a list of bugs that have been published by MySQL, or submit bug reports to MySQL http://www.mysql.com/news-and-events/newsletter/usually publishes a variety of latest news about MySQL.
 

How to view MySQL Help documentation efficiently