Oracle

Instance:is the database service: It can be understood as a service:Multiple processes + memory structureDatabase:Instance + fileRAC: DB cluster　　Multiple instances + files (shared)---at the moment Io is not resolvedMemory structure:Some cache pools,

SELECT INSTR (' aaac ', ' AAC ') from DUAL; --2select SUBSTR (' ABC ', 2, 1) from DUAL; --bselect ' AA ' | | CHR (ASCII (' B ') + 1) from DUAL; --Aacselect * from V$version; SELECT * FROM product_component_version;--query table space Select

#1, select the most efficient table name order The Oracle parser always processes the table from the back of the from right to left, so the from rightmost table will be treated as the driver table precedence, and when there are multiple table

the difference between ORACLE nvarchar2 and varchar2 1, when the text is stored in the NVARCHAR2, a Chinese character can be saved in 10 characters when it is processed in a char (10), and only 10 characters are saved if used in English.   。 2, and

1.castCAST (' Other ' as NVARCHAR2 (30))2.forDeclareV_guidChar( +); Channelidstrsvarchar2(4000):="';beginV_guid:=Sys_guid (); --Delete temp_stocktransdetail; forCinch(SelectChannelid fromChannelwhereRowNum9) Loop Channelidstrs:=Channelidstrs||','

Detailed operation of the Oracle database to modify IP and host namesmodifying IP operations1. Modify the IP address of the host name in the Hosts file.2. Restart the server network service restart3. Be sure to first delete the original monitor emca-

Always wanted to learn Oracle but didn't make up your mind. This time borrowed a book, must learn Oracle.Currently learning Oracle 11g from getting started to mastering Oracle TechnologyThe basic theory of relational databaseData Model :

First of all, the judgment is not really expired. Input statement: SELECT * from Dba_profiles where profile= ' DEFAULT ' and resource_name= ' password_life_time '; If the display Profile -------------------------------------------------

Oracle minus KeywordsThe minus keyword in sqlThere is a minus keyword in SQL that uses two SQL statements to find out the results of the first SQL statement, and then see if the results are in the results of the second SQL statement. If so, the

Update Suzm. Tpms_bndfwdpreissue_ar F Set (F.sec_code,f.pd_tp_code,f.txn_tm,f.inr_inst_id,f.prtfl_code,F.ccy_code,f.clrg_spd_code,f.txn_tp_code,f.sbj_mtr_scr_code,f.sbj_mtr_scr_mkt_tp_code,F.sbj_mtr_scr_pd_tp_code,f.txn_cnter_p_no,f.txn_cnter_p_name,

USEREVN () in Oracle1.USEREVN ()Returns information about the current user environment, opt can be: entryid,sessionid,terminal,isdba,lable,language,client_info,lang,vsize1.ISDBA See if the current user is a DBA if yes returns true sql> select

CREATE TABLE Space[SQL]View Plaincopy Create tablespace ' ' datafile ' ' Size 500M Default storage (Initial 200m Next 50m Minextents 20 Maxextents 500) Online Example:[SQL]View Plaincopy Create

PL/SQL-variables and plsql Variables 1. PL/SQL Introduction PL/SQL is also a program Language called Procedural Language/SQL ). PL/SQL is an extension of oracle's SQL statements. It adds the features of programming languages to the use of common SQL

ORACLE 10g database architecture, oracle10g The ORACLE 10g database ARCHITECTURE (ORACLE 10g (Release 2) ARCHITECTURE) provides a comprehensive, systematic, and advanced introduction to the ORACLE 10g database ARCHITECTURE. If you can fully

DATAGUARD add and modify REDOLOG size, dataguardredolog Dg online log group size change environment (single instance, Centos 6.5X64, oracle 10.2.0.5, filesystem storage) redo online LOGselect * from v $ logfile where type = 'standby '; # The query

ORACLE foreign key and lock, ORACLE In oracle, if the foreign key is not indexed, modification to the parent table will cause the child table to be added with the full table lock. There are two scenarios: 1. Delete the rows in the parent table. If

Oracle users, oracle users Create user ng_zj identified by ng_zjDefault tablespace tbs_testTemporary tablespace tbs_test_tmp;Grant connect to ng_zj;Grant resource to ng_zj;Grant create table to ng_zj;Grant create sequence to ng_zj;Grant create

Oracle Silent Installation Download the oracle installation package: : Note: To download oracle, you must register oracle. Http://download.oracle.com/otn/nt/oracle11g Download two

Detailed process of user interaction with OracleDB Interaction with Oracle DB The following example describes the Oracle database operations at the most basic level. This example shows an Oracle DB configuration in which the user and the

Selecting the most efficient table name sequence for Oracle performance optimization learning notesSelect the most efficient table name sequence (only valid in the rule-based Optimizer) The ORACLE parser processes the table names in the FROM clause