标签:
在mysql的使用过程中, 可能经常会遇到以下问题:
mysql> ? 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 Help Metadata Language Structure Plugins Procedures Storage Engines Table Maintenance Transactions User-Defined Functions Utility
mysql> ? data types You asked for help about help category: "Data Types" For more information, type ‘help <item>‘, where <item> is one of the following topics: 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
mysql> ? int Name: ‘INT‘ Description: INT[(M)] [UNSIGNED] [ZEROFILL] A normal-size integer. The signed range is -2147483648 to 2147483647. The unsigned range is 0 to 4294967295. URL: http://dev.mysql.com/doc/refman/5.5/en/numeric-type-overview.html
mysql> ? functions You asked for help about help category: "Functions" For more information, type ‘help <item>‘, where <item> is one of the following categories: Bit Functions Comparison operators Control flow functions Date and Time Functions Encryption Functions Information Functions Logical operators Miscellaneous Functions Numeric Functions String Functions
mysql> ? Date and Time Functions You asked for help about help category: "Date and Time Functions" For more information, type ‘help <item>‘, where <item> is one of the following topics: 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
mysql> ? show
Name: ‘SHOW‘
Description:
SHOW has many forms that provide information about databases, tables,
columns, or status information about the server. This section describes
those following:
SHOW AUTHORS
SHOW {BINARY | MASTER} LOGS
SHOW BINLOG EVENTS [IN ‘log_name‘] [FROM pos] [LIMIT [offset,] row_count]
SHOW CHARACTER SET [like_or_where]
SHOW COLLATION [like_or_where]
SHOW [FULL] COLUMNS FROM tbl_name [FROM db_name] [like_or_where]
SHOW CONTRIBUTORS
SHOW CREATE DATABASE db_name
SHOW CREATE EVENT event_name
SHOW CREATE FUNCTION func_name
SHOW CREATE PROCEDURE proc_name
SHOW CREATE TABLE tbl_name
SHOW CREATE TRIGGER trigger_name
SHOW CREATE VIEW view_name
SHOW DATABASES [like_or_where]
SHOW ENGINE engine_name {STATUS | MUTEX}
SHOW [STORAGE] ENGINES
SHOW ERRORS [LIMIT [offset,] row_count]
SHOW EVENTS
SHOW FUNCTION CODE func_name
SHOW FUNCTION STATUS [like_or_where]
SHOW GRANTS FOR user
SHOW INDEX FROM tbl_name [FROM db_name]
SHOW MASTER STATUS
SHOW OPEN TABLES [FROM db_name] [like_or_where]
SHOW PLUGINS
SHOW PROCEDURE CODE proc_name
SHOW PROCEDURE STATUS [like_or_where]
SHOW PRIVILEGES
SHOW [FULL] PROCESSLIST
SHOW PROFILE [types] [FOR QUERY n] [OFFSET n] [LIMIT n]
SHOW PROFILES
SHOW SLAVE HOSTS
SHOW SLAVE STATUS
SHOW [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 expr
If the syntax for a given SHOW statement includes a LIKE ‘pattern‘
part, ‘pattern‘ is a string that can contain the SQL "%" and "_"
wildcard characters. The pattern is useful for restricting statement
output to matching values.
Several SHOW statements also accept a WHERE clause that provides more
flexibility in specifying which rows to display. See
http://dev.mysql.com/doc/refman/5.5/en/extended-show.html.
URL: http://dev.mysql.com/doc/refman/5.5/en/show.html
mysql> ? concat
Name: ‘CONCAT‘
Description:
Syntax:
CONCAT(str1,str2,...)
Returns the string that results from concatenating the arguments. May
have one or more arguments. If all arguments are nonbinary strings, the
result is a nonbinary string. If the arguments include any binary
strings, the result is a binary string. A numeric argument is converted
to its equivalent string form. This is a nonbinary string as of MySQL
5.5.3. Before 5.5.3, it is a binary string; to to avoid that and
produce a nonbinary string, you can use an explicit type cast, as in
this example:
SELECT CONCAT(CAST(int_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.html
Examples:
mysql> SELECT CONCAT(‘My‘, ‘S‘, ‘QL‘);
-> ‘MySQL‘
mysql> SELECT CONCAT(‘My‘, NULL, ‘QL‘);
-> NULL
mysql> SELECT CONCAT(14.3);
-> ‘14.3‘
mysql> ? create table
Name: ‘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_statement
Or:
CREATE [TEMPORARY] TABLE [IF NOT EXISTS] tbl_name
{ LIKE old_tbl_name | (LIKE old_tbl_name) }
......
mysql> ? grant
Name: ‘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
......
下面把查看手册和官方资料的地址献上, 就把衣钵都传给你们了, 别忘了给个赞哦~
标签:
原文地址:http://www.cnblogs.com/chenqionghe/p/4834565.html