一 什么是用户进程 用户进程是指用户到 Oracle 数据库服务器的链接，用户进程处理用户输入并通过 Oracle 程序接口与 Oracle 服务器进程通信。用户进程还负责显示用户请求的信息，必要时可以将信息处理成更有用的形式。用户通过客户端，比如 SQL Plus 、 SQL
一 什么是用户进程
用户进程是指用户到Oracle数据库服务器的链接，用户进程处理用户输入并通过Oracle程序接口与Oracle服务器进程通信。用户进程还负责显示用户请求的信息，必要时可以将信息处理成更有用的形式。用户通过客户端，比如SQL Plus、SQL Developer、PL SQL Developer、Toad等工具连接上服务器而产生的进程。
二 怎样查看用户进程
通过视图v$session进行查看。示例：
[oracle@localhost 桌面]$ lsnrctl start LSNRCTL for Linux: Version 10.2.0.1.0 - Production on 27-MAY-2013 19:33:25 Copyright (c) 1991, 2005, Oracle. All rights reserved. Starting /oracle/oracle//product/10.2.0/db_1/bin/tnslsnr: please wait... TNSLSNR for Linux: Version 10.2.0.1.0 - Production System parameter file is /oracle/oracle//product/10.2.0/db_1/network/admin/listener.ora Log messages written to /oracle/oracle//product/10.2.0/db_1/network/log/listener.log Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1))) Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=localhost.localdomain)(PORT=1521))) Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1))) STATUS of the LISTENER ------------------------ Alias LISTENER Version TNSLSNR for Linux: Version 10.2.0.1.0 - Production Start Date 27-MAY-2013 19:33:27 Uptime 0 days 0 hr. 0 min. 0 sec Trace Level off Security ON: Local OS Authentication SNMP OFF Listener Parameter File /oracle/oracle//product/10.2.0/db_1/network/admin/listener.ora Listener Log File /oracle/oracle//product/10.2.0/db_1/network/log/listener.log Listening Endpoints Summary... (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1))) (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=localhost.localdomain)(PORT=1521))) Services Summary... Service "PLSExtProc" has 1 instance(s). Instance "PLSExtProc", status UNKNOWN, has 1 handler(s) for this service... The command completed successfully [oracle@localhost 桌面]$ sqlplus SQL*Plus: Release 10.2.0.1.0 - Production on Mon May 27 19:33:34 2013 Copyright (c) 1982, 2005, Oracle. All rights reserved. Enter user-name: / as sysdba Connected to an idle instance. SQL> startup ORACLE instance started. Total System Global Area 167772160 bytes Fixed Size 1218316 bytes Variable Size 71305460 bytes Database Buffers 92274688 bytes Redo Buffers 2973696 bytes sDatabase mounted. Database opened. SQL> show parameter user_ NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ license_max_users integer 0 user_dump_dest string /oracle/oracle/product/10.2.0/ db_1/admin/orcl/udump SQL> desc v$session; Name Null? Type ----------------------------------------- -------- ---------------------------- SADDR RAW(4) SID NUMBER SERIAL# NUMBER AUDSID NUMBER PADDR RAW(4) USER# NUMBER USERNAME VARCHAR2(30) COMMAND NUMBER OWNERID NUMBER TADDR VARCHAR2(8) LOCKWAIT VARCHAR2(8) STATUS VARCHAR2(8) SERVER VARCHAR2(9) SCHEMA# NUMBER SCHEMANAME VARCHAR2(30) OSUSER VARCHAR2(30) PROCESS VARCHAR2(12) MACHINE VARCHAR2(64) TERMINAL VARCHAR2(30) PROGRAM VARCHAR2(48) TYPE VARCHAR2(10) SQL_ADDRESS RAW(4) SQL_HASH_VALUE NUMBER SQL_ID VARCHAR2(13) SQL_CHILD_NUMBER NUMBER PREV_SQL_ADDR RAW(4) PREV_HASH_VALUE NUMBER PREV_SQL_ID VARCHAR2(13) PREV_CHILD_NUMBER NUMBER MODULE VARCHAR2(48) MODULE_HASH NUMBER ACTION VARCHAR2(32) ACTION_HASH NUMBER CLIENT_INFO VARCHAR2(64) FIXED_TABLE_SEQUENCE NUMBER ROW_WAIT_OBJ# NUMBER ROW_WAIT_FILE# NUMBER ROW_WAIT_BLOCK# NUMBER ROW_WAIT_ROW# NUMBER LOGON_TIME DATE LAST_CALL_ET NUMBER PDML_ENABLED VARCHAR2(3) FAILOVER_TYPE VARCHAR2(13) FAILOVER_METHOD VARCHAR2(10) FAILED_OVER VARCHAR2(3) RESOURCE_CONSUMER_GROUP VARCHAR2(32) PDML_STATUS VARCHAR2(8) PDDL_STATUS VARCHAR2(8) PQ_STATUS VARCHAR2(8) CURRENT_QUEUE_DURATION NUMBER CLIENT_IDENTIFIER VARCHAR2(64) BLOCKING_SESSION_STATUS VARCHAR2(11) BLOCKING_INSTANCE NUMBER BLOCKING_SESSION NUMBER SEQ# NUMBER EVENT# NUMBER EVENT VARCHAR2(64) P1TEXT VARCHAR2(64) P1 NUMBER P1RAW RAW(4) P2TEXT VARCHAR2(64) P2 NUMBER P2RAW RAW(4) P3TEXT VARCHAR2(64) P3 NUMBER P3RAW RAW(4) WAIT_CLASS_ID NUMBER WAIT_CLASS# NUMBER WAIT_CLASS VARCHAR2(64) WAIT_TIME NUMBER SECONDS_IN_WAIT NUMBER STATE VARCHAR2(19) SERVICE_NAME VARCHAR2(64) SQL_TRACE VARCHAR2(8) SQL_TRACE_WAITS VARCHAR2(5) SQL_TRACE_BINDS VARCHAR2(5) SQL> desc v$process; Name Null? Type ----------------------------------------- -------- ---------------------------- ADDR RAW(4) PID NUMBER SPID VARCHAR2(12) USERNAME VARCHAR2(15) SERIAL# NUMBER TERMINAL VARCHAR2(30) PROGRAM VARCHAR2(48) TRACEID VARCHAR2(255) BACKGROUND VARCHAR2(1) LATCHWAIT VARCHAR2(8) LATCHSPIN VARCHAR2(8) PGA_USED_MEM NUMBER PGA_ALLOC_MEM NUMBER PGA_FREEABLE_MEM NUMBER PGA_MAX_MEM NUMBER SQL> desc v$sql; Name Null? Type ----------------------------------------- -------- ---------------------------- SQL_TEXT VARCHAR2(1000) SQL_FULLTEXT CLOB SQL_ID VARCHAR2(13) SHARABLE_MEM NUMBER PERSISTENT_MEM NUMBER RUNTIME_MEM NUMBER SORTS NUMBER LOADED_VERSIONS NUMBER OPEN_VERSIONS NUMBER USERS_OPENING NUMBER FETCHES NUMBER EXECUTIONS NUMBER PX_SERVERS_EXECUTIONS NUMBER END_OF_FETCH_COUNT NUMBER USERS_EXECUTING NUMBER LOADS NUMBER FIRST_LOAD_TIME VARCHAR2(38) INVALIDATIONS NUMBER PARSE_CALLS NUMBER DISK_READS NUMBER DIRECT_WRITES NUMBER BUFFER_GETS NUMBER APPLICATION_WAIT_TIME NUMBER CONCURRENCY_WAIT_TIME NUMBER CLUSTER_WAIT_TIME NUMBER USER_IO_WAIT_TIME NUMBER PLSQL_EXEC_TIME NUMBER JAVA_EXEC_TIME NUMBER ROWS_PROCESSED NUMBER COMMAND_TYPE NUMBER OPTIMIZER_MODE VARCHAR2(10) OPTIMIZER_COST NUMBER OPTIMIZER_ENV RAW(797) OPTIMIZER_ENV_HASH_VALUE NUMBER PARSING_USER_ID NUMBER PARSING_SCHEMA_ID NUMBER PARSING_SCHEMA_NAME VARCHAR2(30) KEPT_VERSIONS NUMBER ADDRESS RAW(4) TYPE_CHK_HEAP RAW(4) HASH_VALUE NUMBER OLD_HASH_VALUE NUMBER PLAN_HASH_VALUE NUMBER CHILD_NUMBER NUMBER SERVICE VARCHAR2(64) SERVICE_HASH NUMBER MODULE VARCHAR2(64) MODULE_HASH NUMBER ACTION VARCHAR2(64) ACTION_HASH NUMBER SERIALIZABLE_ABORTS NUMBER OUTLINE_CATEGORY VARCHAR2(64) CPU_TIME NUMBER ELAPSED_TIME NUMBER OUTLINE_SID NUMBER CHILD_ADDRESS RAW(4) SQLTYPE NUMBER REMOTE VARCHAR2(1) OBJECT_STATUS VARCHAR2(19) LITERAL_HASH_VALUE NUMBER LAST_LOAD_TIME VARCHAR2(38) IS_OBSOLETE VARCHAR2(1) CHILD_LATCH NUMBER SQL_PROFILE VARCHAR2(64) PROGRAM_ID NUMBER PROGRAM_LINE# NUMBER EXACT_MATCHING_SIGNATURE NUMBER FORCE_MATCHING_SIGNATURE NUMBER LAST_ACTIVE_TIME DATE BIND_DATA RAW(2000) SQL> desc v$sqltext; Name Null? Type ----------------------------------------- -------- ---------------------------- ADDRESS RAW(4) HASH_VALUE NUMBER SQL_ID VARCHAR2(13) COMMAND_TYPE NUMBER PIECE NUMBER SQL_TEXT VARCHAR2(64) --sys用户登录，用session查看用户进程 SQL> SELECT username,sid FROM v$session; USERNAME SID ------------------------------ ---------- 149 150 152 155 SYS 159 160 161 162 163 164 165 USERNAME SID ------------------------------ ---------- 166 167 168 169 170 16 rows selected. --再以自建用户wgb登录，再次查看，会发现新增一条记录 SQL> SELECT username, sid from V$SESSION; USERNAME SID ------------------------------ ---------- WGB 147 149 150 152 155 SYS 159 160 161 162 163 164 USERNAME SID ------------------------------ ---------- 165 166 167 168 169 170 17 rows selected.
三 说明
SID：用户进程与服务器端进程进行连接产生的
没有用户名的记录：本身存在的一些连接，比如后台进程
PID：v$process视图进程查询
四 用户进程对DBA管理的作用
如何去控制用户与服务器进行连接的
要不要Oracle的网络客户端
用户进程与服务器进程产生后，是哪个用户产生的
用户进程产生后进行了一些什么工作
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| @Wentasy |
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