Oracle

Operating system authentication means that any user who logs on to the database can connect to the database using "sqlplus/as sysdba.For security reasons, we may need to disable this feature. Of course, if you cannot log on smoothly using the

You cannot log on to the TSP platform .. Later, we restarted tomcat, but still could not log on. After checking, there is a problem with the database. Go to the top of the oracle server. The oracle process occupies a large amount of resources, the

Problem description: Some of my friends often encounter this problem. I clearly entered the correct Chinese character. Why did I find garbled characters on another computer? In fact, this problem occurs when the database performs Character Set

Database PL/SQL script language function learning notes function build syntax rules: create [or replace] function function_name [(parameter,…)] Return datatype is variable declaration; begin statement ;... [Execption statement;…] The end;

1. Download The oralce vm component. A foreign email address is required. For example, 7mt.org does not work in China, nor does it work in a wall. 2. If nfs is used for shared storage, you must grant full permissions. 3. During installation, we

Analysis of OCP question _ 007: synonym synonyms are the alias of the base table. They are defined only in the data dictionary. They do not store synonyms. They provide location transparency for distributed databases. Accessing resources in

Implement fine-grained auditing from Oracle9i, you can use DBMS_FGA to audit the SELECT statement of the specified table, but in 9i, you can only audit the select statement, DML auditing can be implemented in 10 Gb. 1. Before the audit policy takes

Image Copy Incremental Updates (ICIU): concepts (I) limits the use of Redo to reduce the recovery time (ii) Principles of creating an Image Copy of a data file, and then using an Incremental backup set to update the Image Copy: merge a level 1

Oracle foreign key for table data synchronization method 1: When deleting data in a table with a parent-child table relationship, we all know that we need to delete the child table before deleting the data in the parent table, or cancel the foreign

Common Oracle performance-related scripts (SQL) are used in the absence of visual tools to monitor database performance, the following provides several scripts related to Oracle performance for your reference. The following scripts are successfully

Oracle and postgresql join methodFirst, we will introduce several oracle multi-Table Connection Methods:Nested loop: nested loop, which is actually a dual FOR LOOP1. The driver table (External table) and search table (internal table) are divided

Common Oracle functions: nvl/nullif/case when/wm_concat/replace 1. nvl function nvl converts a null value to an actual value. The data type can be date, number, character, and data type must match: nvl (commision, 0) nvl (hiredate, '01-JAN-87 ') nvl

ORA-01659 could not allocate MINEXTENTS over 5 (XXX) solved yesterday's problem with Database Import table: Error: ORA-01659 could not allocate MINEXTENTS 1 over 5 (XXX), try to delete tablespace recreate Delete tablespace: drop tablespace BPM2

The CKPT type of the Oracle checkpoint is used to write the checkpoint to the control file and data file header. Check points are of the following types: Thread checkpoints is the database check point, which may occur in the following cases: closing

If the oracle paging value is greater than or equal to the paging critical point, the SQL code SELECT * FROM (SELECT. *, rownum rn from (select * from t_agent t where t. agent_parent = 20020 and t. agent_state = 0) a where rownum 0; Incorrect: only

Concatenate multiple rows of records in the same column in Oracle into a string [SQL] -- raw data -- a 111 -- B 222 -- a 333 -- a 444 -- B 555 -- final result -- a 111*333*444 SELECT L4.L _ TIME, MAX (SUBSTR (L4. group CONTENT, 2) final field value

This is an oracle function that converts Arabic numerals and Chinese characters. For example, 1234567890.0123 can be converted to "1.2 billion, 34,567,890,", and can also be converted to corresponding numbers.This function supports floating-point

Lost modifications, non-repeated reads, dirty reads, Phantom readsCommon concurrency consistency problems include: Lost modifications, non-repeated reads, dirty reads, and Phantom reads (Phantom reads are often classified as non-repeated reads in

RMAN backup full databaseBackup database; -- backup the entire databaseBackup database format '\ xxxxxx \ xxx _ % U'; -- backs up the entire database to the specified pathBackup tablespace users; -- backup tablespaceBackup datafile 'f: \ ORACLE \

Using Reverse indexes to Improve the Performance of order by desc using reverse indexes (index desc) can greatly improve the performance of SQL statements with order by desc clauses. I. Scenario 1. Table Name: test_t, with a field name: object_id2,