Oracle

To sum up the Oracle array and the Array Used in bulk collect into Oracle, just like using the Object List in JAVA, but slightly different. Declaration is required before each Object is used. The specific implementation is as follows: the SQL code

In-depth understanding of Oracle partition (2 ): the Design and Implementation of the partitioning scheme is an art that pursues comprehensive balance and is full of dialectical and unified philosophy. However, vulnerabilities frequently occur in

Oracle block fault recoveryFault Block Type:1. Physical fault blocks such as data files, control files, and redo logs2: Logical fault blocks, such as table block faults, and a series of logical structuresFirst, we introduce several methods for

Oracle page summary select * from (select. *, rownum row_num from (select * from mytable t order by t. id desc) awhere rownum = 1 order by u_age desc; select * from (select. *, rownum row_num from (select * from mytable t order by t. id desc) a) B

In-depth understanding of Oracle Table (6): differences between heap organization table (HOT) and index organization table (IOT) in-depth understanding of Oracle table (5 ): definition, principle, algorithm, cost, mode, and bitmap of Hash Join http:/

10g rac asm modify IP address first, yesterday set up a set of full raw (including crs and voting disks and database files) 10.2.0.1RAC (not Using asm, the title is written in asm and is used by many comrades. I can modify the method here.) to test

When the oracle11g database is started, the memory_target not supported on this system error solution is reported. The reason is that the shm size of the Linux system is smaller than that set by the SGA. In terms of distance, SGA is set to 4 GB, shm

Oracle reverse indexes, such as create index idx_rev on tiger. test (test_name) reverse, store the index tablespace in a disk architecture that physically splits files into multiple disks. Data is stored with a reverse key index, and the value of

Oracle monitors the tablespace and automatically adds the SQL code of the Data File Script --- create view --- percentage create view tablespace_used_percent as select useage from (select. tablespace_name,. file_name,. total "Total (MB)", round (.

The where condition of oracle has special characters for processing such data: select 'fie _ a' as col from dualunion allselect' fie _ B 'as col from dualunion allselect 'fi _ a' as col from dualunion allselect 'fi _ B' as col from dual; I need to

Row_number () over () analysis function usage row_number () over (partition by col1 order by col2) indicates grouping by col1 and sorting by col2 within the group, the value calculated by this function indicates the sequential numbers after sorting

Oracle JOB inserts SQL code in multiple threads-tested, with a large amount of data inserted, the execution efficiency of multiple threads on a general disk is slower than that of a single insert statement, in the disk array hardware environment,

By default, order by is the ascending order of SQL> select * from dept; (deptno is the ascending order by default)DEPTNO DNAME LOC-------------------------------------10 ACCOUNTING NEW YORK20 RESEARCH DALLAS30 SALES CHICAGO40 OPERATIONS BOSTONDeptno

Multi-layer nested cursor usage in Oracle stored procedures Oracle SQL script code CREATE OR REPLACE PROCEDURE P_DELETE_QK (pId in NUMBER, deep in NUMBER) AS -- pId = classification ID deep = depth, level one_val NUMBER; two_val NUMBER; three_val

Oracle DDL statements use common database objects (tables, views ...); create a table: create table t (a varchar2 (10); select * from t; (delete table) drop table t; varchar2 () can change the length; maximum 4 K; char () Fixed Length string; 8 the

The slightly complex SQL (Oracle) encountered in the project is the first five recycling enterprises in each province. select (select pro. p_name from base_province_list pro where pro. p_index = t. p_index | '100') p_name, entp_name, cnt recycling

Oracle database backup and recovery Script 1: create user: [plain] create temporary tablespace user_temp tempfile 'd: \ app \ topwqp \ oradata \ orcl \ user_temp.dbf 'size 500 m autoextend on next 50 m maxsize 2048 m extent management local; create

Example for understanding join -- group 1st -- this is equivalent to full join. Only SELECT * FROM a, B WHERE. ID = B. ID; SELECT * FROM a JOIN B ON. ID = B. ID; -- 2nd group -- SELECT * FROM a left join B ON. ID = B. id and. NAME = 'a'; SELECT *

The where condition order is different, and the performance is also different. When I saw SQL statement optimization in the book yesterday, the where condition order is different, and the performance is different. Is this recommended for Oracle11G ??

Commonly used Sqlplus commands 1. log on to the system user sqlplus username/password @ Instance name as sysdba 2. create a tablespace create tablespace space name datafile 'file storage physical path 'size 15 M -- storage path of the tablespace,