從SYS_CONTEXT/USERENV讀取所有參數

Question

所以我們在Oracle中有這個SYS_CONTEXT function，它有兩個參數，第一個是命名空間，第二個參數名稱。有一個名爲USERENV的預定義名稱空間，它帶有各種參數，其確切數量和名稱取決於所使用的Oracle版本。

使用Firefox和Firequery你可以從Oracle文檔頁面鏈接到上述所有參數名的列表，像這樣：

$("tr > td[id] > p > code").map(function() { return $(this).text() }) 

然後你可以創建，讀取和輸出整個上下文中的程序 - 至少對於你已經抓取參數的版本。

但是拋開這種靜態閱讀SYS_CONTEXT/USERENV的方式，是否有動態的方式呢？數據字典中的一些地方列出USERENV的有效參數名稱？

至於爲什麼我想閱讀USERENV，這只是爲了閒置的學習目的和好奇心。

Answer 1

無法確定userenv命名空間支持的值。一種方法是創建一個支持參數名稱的表格。

Answer 2

我想這可能對您有所幫助。 下面的查詢將Oracle USERENV上下文轉儲爲表。

select res.* 
    from (
     select * 
     from (
     select 
      sys_context ('userenv','ACTION') ACTION, 
      sys_context ('userenv','AUDITED_CURSORID') AUDITED_CURSORID, 
      sys_context ('userenv','AUTHENTICATED_IDENTITY') AUTHENTICATED_IDENTITY, 
      sys_context ('userenv','AUTHENTICATION_DATA') AUTHENTICATION_DATA, 
      sys_context ('userenv','AUTHENTICATION_METHOD') AUTHENTICATION_METHOD, 
      sys_context ('userenv','BG_JOB_ID') BG_JOB_ID, 
      sys_context ('userenv','CLIENT_IDENTIFIER') CLIENT_IDENTIFIER, 
      sys_context ('userenv','CLIENT_INFO') CLIENT_INFO, 
      sys_context ('userenv','CURRENT_BIND') CURRENT_BIND, 
      sys_context ('userenv','CURRENT_EDITION_ID') CURRENT_EDITION_ID, 
      sys_context ('userenv','CURRENT_EDITION_NAME') CURRENT_EDITION_NAME, 
      sys_context ('userenv','CURRENT_SCHEMA') CURRENT_SCHEMA, 
      sys_context ('userenv','CURRENT_SCHEMAID') CURRENT_SCHEMAID, 
      sys_context ('userenv','CURRENT_SQL') CURRENT_SQL, 
      sys_context ('userenv','CURRENT_SQLn') CURRENT_SQLn, 
      sys_context ('userenv','CURRENT_SQL_LENGTH') CURRENT_SQL_LENGTH, 
      sys_context ('userenv','CURRENT_USER') CURRENT_USER, 
      sys_context ('userenv','CURRENT_USERID') CURRENT_USERID, 
      sys_context ('userenv','DATABASE_ROLE') DATABASE_ROLE, 
      sys_context ('userenv','DB_DOMAIN') DB_DOMAIN, 
      sys_context ('userenv','DB_NAME') DB_NAME, 
      sys_context ('userenv','DB_UNIQUE_NAME') DB_UNIQUE_NAME, 
      sys_context ('userenv','DBLINK_INFO') DBLINK_INFO, 
      sys_context ('userenv','ENTRYID') ENTRYID, 
      sys_context ('userenv','ENTERPRISE_IDENTITY') ENTERPRISE_IDENTITY, 
      sys_context ('userenv','FG_JOB_ID') FG_JOB_ID, 
      sys_context ('userenv','GLOBAL_CONTEXT_MEMORY') GLOBAL_CONTEXT_MEMORY, 
      sys_context ('userenv','GLOBAL_UID') GLOBAL_UID, 
      sys_context ('userenv','HOST') HOST, 
      sys_context ('userenv','IDENTIFICATION_TYPE') IDENTIFICATION_TYPE, 
      sys_context ('userenv','INSTANCE') INSTANCE, 
      sys_context ('userenv','INSTANCE_NAME') INSTANCE_NAME, 
      sys_context ('userenv','IP_ADDRESS') IP_ADDRESS, 
      sys_context ('userenv','ISDBA') ISDBA, 
      sys_context ('userenv','LANG') LANG, 
      sys_context ('userenv','LANGUAGE') LANGUAGE, 
      sys_context ('userenv','MODULE') MODULE, 
      sys_context ('userenv','NETWORK_PROTOCOL') NETWORK_PROTOCOL, 
      sys_context ('userenv','NLS_CALENDAR') NLS_CALENDAR, 
      sys_context ('userenv','NLS_CURRENCY') NLS_CURRENCY, 
      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','NLS_TERRITORY') NLS_TERRITORY, 
      sys_context ('userenv','OS_USER') OS_USER, 
      sys_context ('userenv','POLICY_INVOKER') POLICY_INVOKER, 
      sys_context ('userenv','PROXY_ENTERPRISE_IDENTITY') PROXY_ENTERPRISE_IDENTITY, 
      sys_context ('userenv','PROXY_USER') PROXY_USER, 
      sys_context ('userenv','PROXY_USERID') PROXY_USERID, 
      sys_context ('userenv','SERVER_HOST') SERVER_HOST, 
      sys_context ('userenv','SERVICE_NAME') SERVICE_NAME, 
      sys_context ('userenv','SESSION_EDITION_ID') SESSION_EDITION_ID, 
      sys_context ('userenv','SESSION_EDITION_NAME') SESSION_EDITION_NAME, 
      sys_context ('userenv','SESSION_USER') SESSION_USER, 
      sys_context ('userenv','SESSION_USERID') SESSION_USERID, 
      sys_context ('userenv','SESSIONID') SESSIONID, 
      sys_context ('userenv','SID') SID, 
      sys_context ('userenv','STATEMENTID') STATEMENTID, 
      sys_context ('userenv','TERMINAL') TERMINAL 
     from dual 
     -- where sys_context ('userenv','SESSIONID') NOT in ('SYS', 'XDB') -- <<<<< filter by user 
    ) 
     unpivot include nulls (
     val for name in (action, audited_cursorid, authenticated_identity, authentication_data, authentication_method, bg_job_id, client_identifier, client_info, current_bind, current_edition_id, current_edition_name, current_schema, current_schemaid, current_sql, current_sqln, current_sql_length, current_user, current_userid, database_role, db_domain, db_name, db_unique_name, dblink_info, entryid, enterprise_identity, fg_job_id, global_context_memory, global_uid, host, identification_type, instance, instance_name, ip_address, isdba, lang, language, module, network_protocol, nls_calendar, nls_currency, nls_date_format, nls_date_language, nls_sort, nls_territory, os_user, policy_invoker, proxy_enterprise_identity, proxy_user, proxy_userid, server_host, service_name, session_edition_id, session_edition_name, session_user, session_userid, sessionid, sid, statementid, terminal) 
    ) 
    ) res;