You will understand this statement under execution:
select SYS_CONTEXT ( 'USERENV', 'TERMINAL') terminal, SYS_CONTEXT ( 'USERENV', 'LANGUAGE') language, SYS_CONTEXT ( 'USERENV', 'SESSIONID') sessionid, SYS_CONTEXT ( 'USERENV', 'INSTANCE') instance, SYS_CONTEXT ( 'USERENV', 'ENTRYID') entryid, SYS_CONTEXT ( 'USERENV', 'ISDBA') isdba, SYS_CONTEXT ( 'USERENV', 'NLS_TERRITORY') nls_territory, SYS_CONTEXT ( 'USERENV', 'NLS_CURRENCY') nls_currency, SYS_CONTEXT ( ' USERENV ',' NLS_CALENDAR ') nls_calendar, SYS_CONTEXT (' USERENV ',' NLS_DATE_FORMAT ') nls_date_format, SYS_CONTEXT (' USERENV ',' NLS_DATE_LANGUAGE ') nls_date_language, SYS_CONTEXT (' USERENV ',' NLS_SORT ') nls_sort, SYS_CONTEXT (' USERENV ' , 'CURRENT_USER') current_user, SYS_CONTEXT ( 'USERENV', 'cURRENT_USERID') current_userid, SYS_CONTEXT ( 'USERENV', 'SESSION_USER') session_user, SYS_CONTEXT ( 'USERENV', 'sESSION_USERID') session_userid, SYS_CONTEXT ( 'USERENV', ' pROXY_USER ') proxy_user, SYS_CONTEXT (' USERENV ',' PROXY_USERID ') proxy_userid, SYS_CONTEXT (' USERENV ',' dB_DOMAIN ') db_domain, SYS_CONTEXT (' USERENV ',' dB_NAME ') db_name, SYS_CONTE XT ( 'USERENV', 'HOST') host, SYS_CONTEXT ( 'USERENV', 'OS_USER') os_user, SYS_CONTEXT ( 'USERENV', 'EXTERNAL_NAME') external_name, SYS_CONTEXT ( 'USERENV', 'IP_ADDRESS') ip_address, SYS_CONTEXT ( 'Useerenv', 'network_protocol') Network_protocol, sys_context ('useerenv', 'bg_job_id') bg_job_id, sys_context ('useerenv', 'fg_job_id'
