下列常量由此扩展定义，且仅在此扩展编译入 PHP 或在运行时动态载入时可用。
MYSQLI_READ_DEFAULT_GROUP
Read options from the named group from my.cnf
or the file specified with MYSQLI_READ_DEFAULT_FILE
MYSQLI_READ_DEFAULT_FILE
Read options from the named option file instead of from my.cnf
MYSQLI_OPT_CONNECT_TIMEOUT
Connect timeout in seconds
MYSQLI_OPT_LOCAL_INFILE
Enables command LOAD LOCAL INFILE
MYSQLI_INIT_COMMAND
Command to execute when connecting to MySQL server. Will automatically be re-executed when reconnecting.
MYSQLI_CLIENT_SSL
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
Use compression protocol
MYSQLI_CLIENT_INTERACTIVE
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
Allow spaces after function names. Makes all functions names reserved words.
MYSQLI_CLIENT_NO_SCHEMA
Don't allow the db_name.tbl_name.col_name syntax.
MYSQLI_CLIENT_MULTI_QUERIES
Allows multiple semicolon-delimited queries in a single mysqli_query() call.
MYSQLI_STORE_RESULT
For using buffered resultsets
MYSQLI_USE_RESULT
For using unbuffered resultsets
MYSQLI_ASSOC
Columns are returned into the array having the fieldname as the array index.
MYSQLI_NUM
Columns are returned into the array having an enumerated index.
MYSQLI_BOTH
Columns are returned into the array having both a numerical index and the fieldname as the associative index.
MYSQLI_NOT_NULL_FLAG
Indicates that a field is defined as NOT NULL
MYSQLI_PRI_KEY_FLAG
Field is part of a primary index
MYSQLI_UNIQUE_KEY_FLAG
Field is part of a unique index.
MYSQLI_MULTIPLE_KEY_FLAG
Field is part of an index.
MYSQLI_BLOB_FLAG
Field is defined as BLOB
MYSQLI_UNSIGNED_FLAG
Field is defined as UNSIGNED
MYSQLI_ZEROFILL_FLAG
Field is defined as ZEROFILL
MYSQLI_AUTO_INCREMENT_FLAG
Field is defined as AUTO_INCREMENT
MYSQLI_TIMESTAMP_FLAG
Field is defined as TIMESTAMP
MYSQLI_SET_FLAG
Field is defined as SET
MYSQLI_NUM_FLAG
Field is defined as NUMERIC
MYSQLI_PART_KEY_FLAG
Field is part of an multi-index
MYSQLI_GROUP_FLAG
Field is part of GROUP BY
MYSQLI_TYPE_DECIMAL
Field is defined as DECIMAL
MYSQLI_TYPE_NEWDECIMAL
Precision math DECIMAL or NUMERIC field (MySQL 5.0.3 and up)
MYSQLI_TYPE_BIT
Field is defined as BIT (MySQL 5.0.3 and up)
MYSQLI_TYPE_TINY
Field is defined as TINYINT
MYSQLI_TYPE_SHORT
Field is defined as SMALLINT
MYSQLI_TYPE_LONG
Field is defined as INT
MYSQLI_TYPE_FLOAT
Field is defined as FLOAT
MYSQLI_TYPE_DOUBLE
Field is defined as DOUBLE
MYSQLI_TYPE_NULL
Field is defined as DEFAULT NULL
MYSQLI_TYPE_TIMESTAMP
Field is defined as TIMESTAMP
MYSQLI_TYPE_LONGLONG
Field is defined as BIGINT
MYSQLI_TYPE_INT24
Field is defined as MEDIUMINT
MYSQLI_TYPE_DATE
Field is defined as DATE
MYSQLI_TYPE_TIME
Field is defined as TIME
MYSQLI_TYPE_DATETIME
Field is defined as DATETIME
MYSQLI_TYPE_YEAR
Field is defined as YEAR
MYSQLI_TYPE_NEWDATE
Field is defined as DATE
MYSQLI_TYPE_INTERVAL
Field is defined as INTERVAL
MYSQLI_TYPE_ENUM
Field is defined as ENUM
MYSQLI_TYPE_SET
Field is defined as SET
MYSQLI_TYPE_TINY_BLOB
Field is defined as TINYBLOB
MYSQLI_TYPE_MEDIUM_BLOB
Field is defined as MEDIUMBLOB
MYSQLI_TYPE_LONG_BLOB
Field is defined as LONGBLOB
MYSQLI_TYPE_BLOB
Field is defined as BLOB
MYSQLI_TYPE_VAR_STRING
Field is defined as VARCHAR
MYSQLI_TYPE_STRING
Field is defined as STRING
MYSQLI_TYPE_CHAR
Field is defined as CHAR
MYSQLI_TYPE_GEOMETRY
Field is defined as GEOMETRY
MYSQLI_NEED_DATA
More data available for bind variable
MYSQLI_NO_DATA
No more data available for bind variable
MYSQLI_DATA_TRUNCATED
Data truncation occurred. Available since PHP 5.1.0 and MySQL 5.0.5.
MYSQLI_ENUM_FLAG
Field is defined as ENUM. Available since PHP 5.3.0.
MYSQLI_CURSOR_TYPE_FOR_UPDATE
MYSQLI_CURSOR_TYPE_NO_CURSOR
MYSQLI_CURSOR_TYPE_READ_ONLY
MYSQLI_CURSOR_TYPE_SCROLLABLE
MYSQLI_STMT_ATTR_CURSOR_TYPE
MYSQLI_STMT_ATTR_PREFETCH_ROWS
MYSQLI_STMT_ATTR_UPDATE_MAX_LENGTH
MYSQLI_SET_CHARSET_NAME