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。
MYSQLX_CLIENT_SSL
(int)
MYSQLX_TYPE_DECIMAL
(int)
MYSQLX_TYPE_TINY
(int)
MYSQLX_TYPE_SHORT
(int)
MYSQLX_TYPE_SMALLINT
(int)
MYSQLX_TYPE_MEDIUMINT
(int)
MYSQLX_TYPE_INT
(int)
MYSQLX_TYPE_BIGINT
(int)
MYSQLX_TYPE_LONG
(int)
MYSQLX_TYPE_FLOAT
(int)
MYSQLX_TYPE_DOUBLE
(int)
MYSQLX_TYPE_NULL
(int)
MYSQLX_TYPE_TIMESTAMP
(int)
MYSQLX_TYPE_LONGLONG
(int)
MYSQLX_TYPE_INT24
(int)
MYSQLX_TYPE_DATE
(int)
MYSQLX_TYPE_TIME
(int)
MYSQLX_TYPE_DATETIME
(int)
MYSQLX_TYPE_YEAR
(int)
MYSQLX_TYPE_NEWDATE
(int)
MYSQLX_TYPE_ENUM
(int)
MYSQLX_TYPE_SET
(int)
MYSQLX_TYPE_TINY_BLOB
(int)
MYSQLX_TYPE_MEDIUM_BLOB
(int)
MYSQLX_TYPE_LONG_BLOB
(int)
MYSQLX_TYPE_BLOB
(int)
MYSQLX_TYPE_VAR_STRING
(int)
MYSQLX_TYPE_STRING
(int)
MYSQLX_TYPE_CHAR
(int)
MYSQLX_TYPE_BYTES
(int)
MYSQLX_TYPE_INTERVAL
(int)
MYSQLX_TYPE_GEOMETRY
(int)
MYSQLX_TYPE_JSON
(int)
MYSQLX_TYPE_NEWDECIMAL
(int)
MYSQLX_TYPE_BIT
(int)
MYSQLX_LOCK_DEFAULT
(int)
MYSQLX_LOCK_NOWAIT
(int)
MYSQLX_LOCK_SKIP_LOCKED
(int)