Oracle

Oracle RAC backup and recovery OCR Oracle RAC backup and recovery OCRvoting disks Backup Recovery reference: http://www.bkjia.com/database/201303/195593.html 1. OCR supports two backup methods: automatic backup and manual backup. Automatic Backup:

Oracle exp/imp Data Backup 1. Oracle11g does not allocate segment to empty tables by default. Therefore, empty tables are not exported when exp is used to export Oracle11g databases. Solution: After the deferred_segment_creation parameter is set to

The syntax format of the oracle Lpad function is as follows: lpad (string, padded_length, [pad_string]) string to be filled; the length of the string after padded_length is filled, that is, the length of the string returned by the function, if the

Connect to the ORACLE database through TunnelsSuppose there are two servers on the Internet, one is the application server (Linux), the other is the database server (win2003), and the two servers are in the same LAN (the same network segment ), you

Oracle -- optimizer_mode Oracle uses the Optimizer_mode parameter to control the optimizer preferences. 9i commonly uses several parameters: first_rows, all_rows, first_rows_N, rule, choose, and so on. 10 Gb is less than rule and choose. Oracle has

Oracle statement Exercise 1 switch to the oracle hr user below Exercise 1. query the names and salaries of employees whose salaries are greater than 12000 select first_name, last_name, salary from employees where salary> 12000; 2. query the name and

ADD_MONTHS () What if the second parameter is decimal?We often use the ADD_MONTHS () function to obtain the date of a date after a few months. For example, we want to get the date after two months (January 1, April 05, 2013 ): chenZw> alter session

A cainiao's oracle path -------- II (continued) case 16 which employees do not receive 400,500,100 yuan in bonuses and are not empty. [SQL] select ename, bonus from emp_xxx where bonus not in () or bonus is null; // when not in is used for

Obtain the field information of the oracle table structure. select. column_id as column number,. column_name as column name,. data_type as type, decode (. data_type, 'number',. data_precision,. data_length) as length,. data_scale as decimal point,

Oracle scalar quantum query ORACLE allows a single-row subquery to be included in the select clause. Using scalar quantum query can effectively improve performance. When using external connections or using aggregate functions, we can consider the

Sqlplus learning notes (2) set the length of the line to 200 characters and then line feed [SQL] set linesize 200 note: Sqlplus command does not need to write ";" Semicolon SQL statement must end with a semicolon, the Sqlplus command can be used as

Greenplum manages indexes. Considering the characteristics of OLAP systems, you should use indexes carefully and conservatively. Avoid using indexes on frequently updated columns; use B-tree indexes on highly selective columns; and use Bitmap

Using ibatis to migrate databases from oracle to mysql. Our project needs to migrate data from oracle to mysql under the company's big strategy. Our project uses ibatis, some modifications required on the ibatis layer are as follows: the unit test

Oracle rac ssh equivalence configuration (I). To facilitate communications between nodes in the RAC environment, you must configure the SSH equivalence statement: when a user or program is connected from one machine to another without a password,

Instant Client for linux sometime for some reason, ex. you can't install on the host, not get the install package, or others. but you want connnect the oracle database via sqlplus only, in times you can use oracle Instant Client, the package very

Oracle copy and postgresql copy introduce oracle copy first. In fact, this command has never been used till now and is also used for data migration. Note that this command is a SQL * PLUS command, it is not from oracle. You can use this command to

One of the database query optimizations is to process more than one million data to increase the query speed: 1. Avoid using the where clause as much as possible! = Or <> operator. Otherwise, the engine will discard the index for full table scanning.

Oracle has a very practical way of implementing summary reports. In the financial system or other report statistics function, I want to have a lot of cases similar to the following report. With the grouping_id function, it will be easy to implement,

Automatically generate the AWR report [plain] create or replace procedure sp_auto_awrreport (reporttime varchar2 default null, rpt_interval number default 2) AS ---- purpose: automatically generate the AWR report ---- Creator: cavlin ---- creation

Oracle 11.2 create a database on a bare device 1 Overview .... 12. Install the database software .. 13. Create a database using the script .. 14 confirm the information after completion .. 3 1 Overview Oracle 11.2 Oracle Universal Installer (OUI)