LXXXVI. MySQL Improved Extension
简介
The mysqli extension allows you to access the functionality provided by MySQL 4.1 and above. More information about the MySQL Database server can be found at http://www.mysql.com/
Documentation for MySQL can be found at http://dev.mysql.com/doc/.
Parts of this documentation included from MySQL manual with permissions of MySQL AB.
需求
In order to have these functions available, you must compile PHP with support for the mysqli extension.
注: The mysqli extension is designed to work with the version 4.1.3 or above of MySQL. For previous versions, please see the MySQL extension documentation.
安装
To install the mysqli extension for PHP, use the --with-mysqli=mysql_config_path/mysql_config configuration option where mysql_config_path represents the location of the mysql_config program that comes with MySQL versions greater than 4.1.
If you would like to install the mysql extension along with the mysqli extension you have to use the same client library to avoid any conflicts.
运行时配置
这些函数的行为受 php.ini 的影响。
表格 1. MySQLi Configuration Options
| Name | Default | Changeable | Changelog |
|---|---|---|---|
| mysqli.max_links | "-1" | PHP_INI_SYSTEM | Available since PHP 5.0.0. |
| mysqli.default_port | "3306" | PHP_INI_ALL | Available since PHP 5.0.0. |
| mysqli.default_socket | NULL | PHP_INI_ALL | Available since PHP 5.0.0. |
| mysqli.default_host | NULL | PHP_INI_ALL | Available since PHP 5.0.0. |
| mysqli.default_user | NULL | PHP_INI_ALL | Available since PHP 5.0.0. |
| mysqli.default_pw | NULL | PHP_INI_ALL | Available since PHP 5.0.0. |
For further details and definitions of the above PHP_INI_* constants, see the chapter on configuration changes.
以下是配置选项的简要解释。
- mysqli.max_links integer
The maximum number of MySQL connections per process.
- mysqli.default_port string
The default TCP port number to use when connecting to the database server if no other port is specified. If no default is specified, the port will be obtained from the MYSQL_TCP_PORT environment variable, the mysql-tcp entry in /etc/services or the compile-time MYSQL_PORT constant, in that order. Win32 will only use the MYSQL_PORT constant.
- mysqli.default_socket string
The default socket name to use when connecting to a local database server if no other socket name is specified.
- mysqli.default_host string
The default server host to use when connecting to the database server if no other host is specified. Doesn't apply in safe mode.
- mysqli.default_user string
The default user name to use when connecting to the database server if no other name is specified. Doesn't apply in safe mode.
- mysqli.default_pw string
The default password to use when connecting to the database server if no other password is specified. Doesn't apply in safe mode.
预定义类
mysqli
Represents a connection between PHP and a MySQL database.
方法
autocommit - turns on or off auto-commiting database modifications
change_user - changes the user of the specified database connection
character_set_name - returns the default character set for the database connection
close - closes a previously opened connection
commit - commits the current transaction
connect - opens a new connection to MySQL database server
debug - performs debugging operations
dump_debug_info - dumps debug information
get_client_info - returns client version
get_host_info - returns type of connection used
get_server_info - returns version of the MySQL server
get_server_version - returns version of the MySQL server
init - initializes mysqli object
info - retrieves information about the most recently executed query
kill - asks the server to kill a mysql thread
multi_query - performs multiple queries
more_results - check if more results exist from currently executed multi-query
next_result - reads next result from currently executed multi-query
options - set options
ping - pings a server connection or reconnects if there is no connection
prepare - prepares a SQL query
query - performs a query
real_connect - attempts to open a connection to MySQL database server
escape_string - escapes special characters in a string for use in a SQL statement, taking into account the current charset of the connection
rollback - rolls back the current transaction
select_db - selects the default database
set_charset - sets the default client character set
ssl_set - sets ssl parameters
stat - gets the current system status
stmt_init- initializes a statement for use with mysqli_stmt_prepare
store_result - transfers a resultset from last query
use_result - transfers an unbuffered resultset from last query
thread_safe - returns whether thread safety is given or not
属性
affected_rows - gets the number of affected rows in a previous MySQL operation
client_info - returns the MySQL client version as a string
client_version - returns the MySQL client version as an integer
errno - returns the error code for the most recent function call
error - returns the error string for the most recent function call
field_count - returns the number of columns for the most recent query
host_info - returns a string representing the type of connection used
info - retrieves information about the most recently executed query
insert_id - returns the auto generated id used in the last query
protocol_version - returns the version of the MySQL protocol used
sqlstate - returns a string containing the SQLSTATE error code for the last error
thread_id - returns the thread ID for the current connection
warning_count - returns the number of warnings generated during execution of the previous SQL statement
mysqli_stmt
Represents a prepared statement.
方法
bind_param - binds variables to a prepared statement
bind_result - binds variables to a prepared statement for result storage
close - closes a prepared statement
data_seek - seeks to an arbitrary row in a statement result set
execute - executes a prepared statement
fetch - fetches result from a prepared statement into bound variables
free_result - frees stored result memory for the given statement handle
result_metadata - retrieves a resultset from a prepared statement for metadata information
prepare - prepares a SQL query
send_long_data - sends data in chunks
reset - resets a prepared statement
store_result - buffers complete resultset from a prepared statement
属性
affected_rows - returns affected rows from last statement execution
errno - returns errorcode for last statement function
errno - returns errormessage for last statement function
param_count - returns number of parameter for a given prepare statement
sqlstate - returns a string containing the SQLSTATE error code for the last statement function
mysqli_result
Represents the result set obtained from a query against the database.
方法
close - closes resultset
data_seek - moves internal result pointer
fetch_field - gets column information from a resultset
fetch_fields - gets information for all columns from a resulset
fetch_field_direct - gets column information for specified column
fetch_array - fetches a result row as an associative array, a numeric array, or both.
fetch_assoc - fetches a result row as an associative array
fetch_object - fetches a result row as an object
fetch_row - gets a result row as an enumerated array
close - frees result memory
field_seek - set result pointer to a specified field offset
属性
current_field - returns offset of current fieldpointer
field_count - returns number of fields in resultset
lengths - returns an array of columnlengths
num_rows - returns number of rows in resultset
预定义常量
表格 2. MySQLi Constants
| Name | Description |
|---|---|
| MYSQLI_READ_DEFAULT_GROUP (integer) | Read options from the named group from `my.cnf' or the file specified with MYSQLI_READ_DEFAULT_FILE |
| MYSQLI_READ_DEFAULT_FILE (integer) | Read options from the named option file instead of from my.cnf |
| MYSQLI_OPT_CONNECT_TIMEOUT (integer) | Connect timeout in seconds |
| MYSQLI_OPT_LOCAL_INFILE (integer) | Enables command LOAD LOCAL INFILE |
| MYSQLI_INIT_COMMAND (integer) | Command to execute when connecting to MySQL server. Will automatically be re-executed when reconnecting. |
| MYSQLI_CLIENT_SSL (integer) | Use SSL (encrypted protocol). This option should not be set by application programs; it is set internally in the MySQL client library |
| MYSQLI_CLIENT_COMPRESS (integer) | Use compression protocol |
| MYSQLI_CLIENT_INTERACTIVE (integer) | Allow interactive_timeout seconds (instead of wait_timeout seconds) of inactivity before closing the connection. The client's session wait_timeout variable will be set to the value of the session interactive_timeout variable. |
| MYSQLI_CLIENT_IGNORE_SPACE (integer) | Allow spaces after function names. Makes all functions names reserved words. |
| MYSQLI_CLIENT_NO_SCHEMA (integer) | Don't allow the db_name.tbl_name.col_name syntax. |
| MYSQLI_CLIENT_MULTI_QUERIES (integer) | |
| MYSQLI_STORE_RESULT (integer) | For using buffered resultsets |
| MYSQLI_USE_RESULT (integer) | For using unbuffered resultsets |
| MYSQLI_ASSOC (integer) | Columns are returned into the array having the fieldname as the array index. |
| MYSQLI_NUM (integer) | Columns are returned into the array having an enumerated index. |
| MYSQLI_BOTH (integer) | Columns are returned into the array having both a numerical index and the fieldname as the associative index. |
| MYSQLI_NOT_NULL_FLAG (integer) | Indicates that a field is defined as NOT NULL |
| MYSQLI_PRI_KEY_FLAG (integer) | Field is part of a primary index |
| MYSQLI_UNIQUE_KEY_FLAG (integer) | Field is part of an unique index. |
| MYSQLI_MULTIPLE_KEY_FLAG (integer) | Field is part of an index. |
| MYSQLI_BLOB_FLAG (integer) | Field is defined as BLOB |
| MYSQLI_UNSIGNED_FLAG (integer) | Field is defined as UNSIGNED |
| MYSQLI_ZEROFILL_FLAG (integer) | Field is defined as ZEROFILL |
| MYSQLI_AUTO_INCREMENT_FLAG (integer) | Field is defined as AUTO_INCREMENT |
| MYSQLI_TIMESTAMP_FLAG (integer) | Field is defined as TIMESTAMP |
| MYSQLI_SET_FLAG (integer) | Field is defined as SET |
| MYSQLI_NUM_FLAG (integer) | Field is defined as NUMERIC |
| MYSQLI_PART_KEY_FLAG (integer) | Field is part of an multi-index |
| MYSQLI_GROUP_FLAG (integer) | Field is part of GROUP BY |
| MYSQLI_TYPE_DECIMAL (integer) | Field is defined as DECIMAL |
| MYSQLI_TYPE_TINY (integer) | Field is defined as TINYINT |
| MYSQLI_TYPE_SHORT (integer) | Field is defined as INT |
| MYSQLI_TYPE_LONG (integer) | Field is defined as INT |
| MYSQLI_TYPE_FLOAT (integer) | Field is defined as FLOAT |
| MYSQLI_TYPE_DOUBLE (integer) | Field is defined as DOUBLE |
| MYSQLI_TYPE_NULL (integer) | Field is defined as DEFAULT NULL |
| MYSQLI_TYPE_TIMESTAMP (integer) | Field is defined as TIMESTAMP |
| MYSQLI_TYPE_LONGLONG (integer) | Field is defined as BIGINT |
| MYSQLI_TYPE_INT24 (integer) | Field is defined as MEDIUMINT |
| MYSQLI_TYPE_DATE (integer) | Field is defined as DATE |
| MYSQLI_TYPE_TIME (integer) | Field is defined as TIME |
| MYSQLI_TYPE_DATETIME (integer) | Field is defined as DATETIME |
| MYSQLI_TYPE_YEAR (integer) | Field is defined as YEAR |
| MYSQLI_TYPE_NEWDATE (integer) | Field is defined as DATE |
| MYSQLI_TYPE_ENUM (integer) | Field is defined as ENUM |
| MYSQLI_TYPE_SET (integer) | Field is defined as SET |
| MYSQLI_TYPE_TINY_BLOB (integer) | Field is defined as TINYBLOB |
| MYSQLI_TYPE_MEDIUM_BLOB (integer) | Field is defined as MEDIUMBLOB |
| MYSQLI_TYPE_LONG_BLOB (integer) | Field is defined as LONGBLOB |
| MYSQLI_TYPE_BLOB (integer) | Field is defined as BLOB |
| MYSQLI_TYPE_VAR_STRING (integer) | Field is defined as VARCHAR |
| MYSQLI_TYPE_STRING (integer) | Field is defined as CHAR |
| MYSQLI_TYPE_GEOMETRY (integer) | Field is defined as GEOMETRY |
| MYSQLI_NEED_DATA (integer) | More data available for bind variable |
| MYSQLI_NO_DATA (integer) | No more data available for bind variable |
| MYSQLI_DATA_TRUNCATED (integer) | Data truncation occurred. Available since PHP 5.1.0 and MySQL 5.0.5. |
Examples
All Examples in the MySQLI documentation use the world database from MySQL AB. The world database can be found at http://dev.mysql.com/get/Downloads/Manual/world.sql.gz/from/pick
- 目录
- mysqli_affected_rows -- Gets the number of affected rows in a previous MySQL operation
- mysqli_autocommit -- Turns on or off auto-commiting database modifications
- mysqli_bind_param -- Alias for mysqli_stmt_bind_param()
- mysqli_bind_result -- Alias for mysqli_stmt_bind_result()
- mysqli_change_user -- Changes the user of the specified database connection
- mysqli_character_set_name -- Returns the default character set for the database connection
- mysqli_client_encoding -- Alias of mysqli_character_set_name()
- mysqli_close -- Closes a previously opened database connection
- mysqli_commit -- Commits the current transaction
- mysqli_connect_errno -- Returns the error code from last connect call
- mysqli_connect_error -- Returns a string description of the last connect error
- mysqli_connect -- Open a new connection to the MySQL server
- mysqli_data_seek -- Adjusts the result pointer to an arbitary row in the result
- mysqli_debug -- Performs debugging operations
- mysqli_disable_reads_from_master -- Disable reads from master
- mysqli_disable_rpl_parse -- Disable RPL parse
- mysqli_dump_debug_info -- Dump debugging information into the log
- mysqli_embedded_connect -- Open a connection to an embedded mysql server
- mysqli_enable_reads_from_master -- Enable reads from master
- mysqli_enable_rpl_parse -- Enable RPL parse
- mysqli_errno -- Returns the error code for the most recent function call
- mysqli_error -- Returns a string description of the last error
- mysqli_escape_string -- Alias of mysqli_real_escape_string()
- mysqli_execute -- Alias for mysqli_stmt_execute()
- mysqli_fetch_array -- Fetch a result row as an associative, a numeric array, or both
- mysqli_fetch_assoc -- Fetch a result row as an associative array
- mysqli_fetch_field_direct -- Fetch meta-data for a single field
- mysqli_fetch_field -- Returns the next field in the result set
- mysqli_fetch_fields -- Returns an array of objects representing the fields in a result set
- mysqli_fetch_lengths -- Returns the lengths of the columns of the current row in the result set
- mysqli_fetch_object -- Returns the current row of a result set as an object
- mysqli_fetch_row -- Get a result row as an enumerated array
- mysqli_fetch -- Alias for mysqli_stmt_fetch()
- mysqli_field_count -- Returns the number of columns for the most recent query
- mysqli_field_seek -- Set result pointer to a specified field offset
- mysqli_field_tell -- Get current field offset of a result pointer
- mysqli_free_result -- Frees the memory associated with a result
- mysqli_get_client_info -- Returns the MySQL client version as a string
- mysqli_get_client_version -- Get MySQL client info
- mysqli_get_host_info -- Returns a string representing the type of connection used
- mysqli_get_metadata -- Alias for mysqli_stmt_result_metadata()
- mysqli_get_proto_info -- Returns the version of the MySQL protocol used
- mysqli_get_server_info -- Returns the version of the MySQL server
- mysqli_get_server_version -- Returns the version of the MySQL server as an integer
- mysqli_info -- Retrieves information about the most recently executed query
- mysqli_init -- Initializes MySQLi and returns a resource for use with mysqli_real_connect()
- mysqli_insert_id -- Returns the auto generated id used in the last query
- mysqli_kill -- Asks the server to kill a MySQL thread
- mysqli_master_query -- Enforce execution of a query on the master in a master/slave setup
- mysqli_more_results -- Check if there any more query results from a multi query
- mysqli_multi_query -- Performs a query on the database
- mysqli_next_result -- Prepare next result from multi_query
- mysqli_num_fields -- Get the number of fields in a result
- mysqli_num_rows -- Gets the number of rows in a result
- mysqli_options -- Set options
- mysqli_param_count -- Alias for mysqli_stmt_param_count()
- mysqli_ping -- Pings a server connection, or tries to reconnect if the connection has gone down
- mysqli_prepare -- Prepare a SQL statement for execution
- mysqli_query -- Performs a query on the database
- mysqli_real_connect -- Opens a connection to a mysql server
- mysqli_real_escape_string -- Escapes special characters in a string for use in a SQL statement, taking into account the current charset of the connection
- mysqli_real_query -- Execute an SQL query
- mysqli_report -- Enables or disables internal report functions
- mysqli_rollback -- Rolls back current transaction
- mysqli_rpl_parse_enabled -- Check if RPL parse is enabled
- mysqli_rpl_probe -- RPL probe
- mysqli_rpl_query_type -- Returns RPL query type
- mysqli_select_db -- Selects the default database for database queries
- mysqli_send_long_data -- Alias for mysqli_stmt_send_long_data()
- mysqli_send_query -- Send the query and return
- mysqli_server_end -- Shut down the embedded server
- mysqli_server_init -- Initialize embedded server
- mysqli_set_charset -- Sets the default client character set
- mysqli_set_opt -- Alias of mysqli_options()
- mysqli_sqlstate -- Returns the SQLSTATE error from previous MySQL operation
- mysqli_ssl_set -- Used for establishing secure connections using SSL
- mysqli_stat -- Gets the current system status
- mysqli_stmt_affected_rows -- Returns the total number of rows changed, deleted, or inserted by the last executed statement
- mysqli_stmt_bind_param -- Binds variables to a prepared statement as parameters
- mysqli_stmt_bind_result -- Binds variables to a prepared statement for result storage
- mysqli_stmt_close -- Closes a prepared statement
- mysqli_stmt_data_seek -- Seeks to an arbitray row in statement result set
- mysqli_stmt_errno -- Returns the error code for the most recent statement call
- mysqli_stmt_error -- Returns a string description for last statement error
- mysqli_stmt_execute -- Executes a prepared Query
- mysqli_stmt_fetch -- Fetch results from a prepared statement into the bound variables
- mysqli_stmt_free_result -- Frees stored result memory for the given statement handle
- mysqli_stmt_init -- Initializes a statement and returns an object for use with mysqli_stmt_prepare
- mysqli_stmt_num_rows -- Return the number of rows in statements result set
- mysqli_stmt_param_count -- Returns the number of parameter for the given statement
- mysqli_stmt_prepare -- Prepare a SQL statement for execution
- mysqli_stmt_reset -- Resets a prepared statement
- mysqli_stmt_result_metadata -- Returns result set metadata from a prepared statement
- mysqli_stmt_send_long_data -- Send data in blocks
- mysqli_stmt_sqlstate -- Returns SQLSTATE error from previous statement operation
- mysqli_stmt_store_result -- Transfers a result set from a prepared statement
- mysqli_store_result -- Transfers a result set from the last query
- mysqli_thread_id -- Returns the thread ID for the current connection
- mysqli_thread_safe -- Returns whether thread safety is given or not
- mysqli_use_result -- Initiate a result set retrieval
- mysqli_warning_count -- Returns the number of warnings from the last query for the given link