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1¡¢ USERENV(OPTION)
¡¡¡¡·µ»Øµ±Ç°µÄ»á»°ÐÅÏ¢.
¡¡¡¡OPTION='ISDBA'Èôµ±Ç°ÊÇDBA½ÇÉ«,ÔòΪTRUE,·ñÔòFALSE.
¡¡¡¡OPTION='LANGUAGE'·µ»ØÊý¾Ý¿âµÄ×Ö·û¼¯.
¡¡¡¡OPTION='SESSIONID'Ϊµ±Ç°»á»°±êʶ·û.
¡¡¡¡OPTION='ENTRYID'·µ»Ø¿ÉÉó¼ÆµÄ»á»°±êʶ·û.
¡¡¡¡OPTION='LANG'·µ»Ø»á»°ÓïÑÔÃû³ÆµÄISO¼ò¼Ç.
¡¡¡¡OPTION='INSTANCE'·µ»Øµ±Ç°µÄʵÀý.
OPTION='terminal'·µ»Øµ±Ç°¼ÆËã»úÃû
¡¡¡¡SELECT USERENV('LANGUAGE') from DUAL;
2¡¢sys_context
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_CONTEXT('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('USERENV','NETWORK_PROTOCOL') network_protocol,
SYS_CONTEXT('USERENV','BG_JOB_ID') bg_job_id,
SYS_CONTEXT('USERENV','FG_JOB_ID') fg_job_id,
SYS_CONTEXT('USERENV','AUTHENTICATION_TYPE') authentication_type,
SYS_CONTEX
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select segment_name, bytes
from user_segments
where segment_type = 'TABLE';
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Select Segment_Name,Sum(bytes)/1024/1024 from User_Extents Group By Segment_Name
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