Oracle

Link: Oracle notes (1) Oracle introduction and installation: http://www.bkjia.com/database/201209/154049.html#oraclenote (2) SQLPlus command example (3) Scott user's table structure example (4) simple query, limited query, and data sorting

In Oracle, the method for disconnecting a user is to first find the current process of the target user. Note that the process is serial # Instead of serial. Some introductions on the Internet miss the #: select sid, serial # from v $ session where

Summary of oracle simple learning (1) -- SQL SQL language classification function example Database Control Language (DCL) controls access to the database, GRANT, REVOKE, and other statement database definition languages (DDL) that authorize and

Step 1: view the table space usage in Oracle: SQL code www.2cto.com select dbf. tablespace_name, dbf. totalspace "Total (M)", dbf. total totalblocks as blocks, dfs. freespace "total remaining amount (M)", dfs. freeblocks "remaining blocks", (dfs.

Oracle forces the user to force the deletion of the associated session www.2cto.com Java code DECLARE u_sid varchar2 (50); u_serialnumber varchar2 (50); u_name varchar2 (50); CURSOR c1 IS select trim (s. sid), trim (s. serial #) from v $ session s,

Delete an oracle database in a linux operating system. turn off the oracle server and background processesps-ef | grep ora www.2cto.com turn off the database shutdown immediate2. turn off the listener lsnrctl status and execute lsnrctl stop if it is

Oracle resets sequence Statement 1 SQL code www.2cto.com DECLARE n NUMBER (10); tsql VARCHAR2 (100); p_seqName varchar2 (20); BEGIN p_seqName: = 'seq _ RUN_ID '; execute immediate 'select' | p_seqName | '. nextval from dual 'into n; n: =-(n-1); tsql:

Custom oracle throws an exception to solve database exceptions throw Caused by: java. SQL. SQLException: ORA-02291: violation of complete constraints (xxx. FK_yyyy)-the parent keyword www.2cto.com is not found. How can I customize the exception

Oracle 11g2 listeners can be registered in two ways: Dynamic and Static. The status of the dynamically registered service in lsnrctl status is ready, and the static service is unknown. In versions earlier than 11g2, the listener is configured

Example 1. example of update lock generation: www.2cto.com session 1: SQL> drop table t purge; SQL> create table t (id int primary key); Table created. SQL> select sid from v $ mystat where rownum = 1; SID ---------- 854 SQL> insert into t values (1)

Oracle learning 3 (Multi-Table query) queries a table: www.2cto.com multi-Table query: the query content is in two tables, and an alias can be created for two tables. Query the name, salary, and Department of the employee, and sort them by

In Linux, add an Oracle scott account. In Linux, the oracle scott Demo mode is located in the directory $ ORACLE_HOME/rdbms/admin/utlsampl. SQL, add steps: Run www.2cto.com in SQL * plus (note that it is under the sys user) @ $

The last DML time on the row in the oracle query table introduces a pseudo column ORA_ROWSCN provided by oracle starting from 10 Gb, it can be divided into two modes: block-based, which is the default mode (block-level tracking), and row-based, in

Oracle SQL-UPDATE, DELETE, INSERT optimization and usage tips UPDATE www.2cto.com 1. Back up data first (secure and improve performance ). 2. Batch update and batch commit to prevent lock tables. 3. If the updated index automatically has a large

Start and Stop services at oracle11g, modify character sets, import and export, create and delete tablespaces, and uninstall oracle. [start and stop the service] // start and stop listening for www.2cto.com lsnrctl start; lsnrctl stop; // start and

How to Understand the latch and enqueue lock problems in Oracle databases. Everyone may have different ideas and different starting points, what is the cause of lock & latch. Then explain the nature of lock & latch from different perspectives.

Oracle Auto-Shared Memory Management (ASMM) starts from Oracle 10 Gb. Oracle provides new features of Automatic SGA Management (ASMM for short, that is, Automatic Shared Memory Management. The so-called ASMM means that we no longer need to manually

Oracle archive data query (partition query) the SQL statement used to query 201212 month data records is as follows: SQL code www.2cto.com SELECT COUNT (DISTINCT (c. caller_nbr) AS emp_use_count FROM tab_pub_calllog c WHERE TO_CHAR (c. end_time,

When analyzing the event enq TX row lock contention Analysis in the Oracle database performance report AWRRPT, it is found that the top 5 tasks waiting for the event first are enq: TX-row lock contention. Www.2cto.com Rpt code Top 5 Timed Events

Oracle SQL writes a method to determine whether a string is a function in the target string based on requirements. Used to identify the following situations: Determine whether string A exists in string B separated by commas (,), for example: