caviar 2850

First, the Linux system initialization processII. Process Management1, Top (real-time display system information)[email protected] ~]# Top2. Free (show memory usage status)FreeThe value of three red boxes is added to the total amount of memory used = blue box used blue Box used + blue Box free = Blue box Totalbuffer[buffer]: memory is used when writing data to diskcache[Cache]: used when the CPU reads data from memory3, PS (shows the status of the current process)PS grep ' Gnome ' # based o

//Launch Oracle# Service Oracle Stop//Turn off Oracle# Service Oracle Restart//Restart Oracle7. TestingA. Boot from bootLast Login:mon 19:57:06-10.0.0.145[[emailprotected] ~]# su-oracle[[emailprotected] ~]$ sql Plus "/as sysdba" Sql*plus:release 10.2.0.1.0-production on Mon Nov 20:07:33 2012Copyright (c) 1982, 2005, ORACLE.NB Sp All rights reserved. Connected to:oracle Database 10g Enterprise Edition Release 10.2.0.1.0-productionwith The partitioning, OLAP and Data Mi Ning Optionssql> set linesi

/s txcmp/s rxmcst/s12:10:01 AM Lo 0.00 0.00 0.00 0.00 0.00 0.00 0.0012:10:01 AM eth0 0.62 0.04 0.04 0.01 0.00 0.00 0.0012:10:01 AM eth1 0.59 0.01 0.04 0.00 0.00 0.00 0.00RXPCK/S indicates the number of packets received per second txpck/s Indicates the number of packets per second rxkb/s amount of data received per second txkb/s amount of data sent per second5 free View memory conditionTotal used free shared buffers cachedmem:1906900 274296 1632604 232 24268 111232-/+ buffers/cache:138796 176810

video sharing website Http://blog.sina.com.cn/s/blog_537b2c0301009hw0.html Nagios surveillance Squid Http://www.hilinux.com/bbs/thread-895-1-1.html Cached Dynamic in PHP squid Http://www.wangchao.net.cn/bbsdetail_1887900.html One of the simplest CDN cases, North-South diversion, smart DNS Http://www.vrlinux.com/show-3-1.html CDN Squid Reverse proxy configuration http://www.dongguanjie.net.cn/blogview.asp?logID=140 Encryption squid.conf Http://hi.baidu.com/webcdn/blog/item/98e4eaec82c70c39269791

(*), sum (SAL) from Scott.emp GROUP by DEPTNO has NT (*) >=5; DEPTNO COUNT (*) SUM (SAL) --------- --------- --------- 20 5 10875 30 6 9400 Sql> Select Deptno,count (*), sum (SAL) from Scott.emp has the have count (*) >=5 GROUP by TNO; DEPTNO COUNT (*) SUM (SAL) --------- --------- --------- 20 5 10875 30 6 9400 67.ORDER by is used to sort the results of the query to output Sql> Select Deptno,ename,sal from scott.emp to Deptno,sal desc; DEPTNO ename SAL --------- ---------- -------

7839 02-apr-81 2975 MARTIN salesman 7698 28-sep-81 1250 1400 BLAKE MANAGER 7839 01-may-81 2850-Clar K MANAGER 7839 09-jun-81 2450 SCOTT ANALYST 7566 19-apr-87 3000 KING PRESIDENT 17-nov-81 5000-TUR NER salesman 7698 08-sep-81 1500 0 ADAMS clerk 7788 23-may-87 1100 JAMES Clerk 7698 03-dec-81 950 FORD ANALYST 7566 03-dec-81 3000 MILLER clerk 7782 23- JAN-82 1300 rows selected. Sql> B. Service Oracle Stop Sql> disconnected f

Employee_id,last_name,first_name,salary from Employee where salary>[$sal] Running in Sqlplus Sql> @c:\1.sql Please input salary (weekly): 1000 Old 2:where Salary>sal New 2:where salary> 1000 employee_id last_name first_name SALARY ----------------- ------------------- ----------------------------- ---------- 7499 ALLEN KEVIN 1600 7505 DOYLE JEAN 2850 7506 DENNIS LYNN 2750 7507 BAKER LESLIE 2200 7521 WARD CYNTHIA 1250 7555 PETERS DANIEL 1250 7557 SHA

Because of the computer room NS firewall Some temporary small problem, Saturday morning to do the car to the West railway station Unicom computer room to adjust, in the inspection of other server hardware when found a DELL PE 2850 server Front of the display screen flashing orange, which means that there are problems The error code displayed on the screen is as follows: IB110 SBE Log Disabled On the Internet to check the key words: Some say it ha

length, purple is value A. Select the PSE Environment: select 1PAY. SYS. DDF01 file t:00 A4 0E (2E), 2E 44 44 46 30 31 00 c:6f 0E, 2E, 2E, A5, 5F 2D, 7A, BF, 0C, 9F, 4D, 0B, 0A 90 00 Card Return Data parsing: 6F (0E), 2E, 2E (1PAY). SYS. DDF01) A5 (SFI short file identifier) 5F 2D (Preferred language) 027A (en Chinese) BF 0C 9F 4D 0B 0A (SW1, SW2) The next step is to read the record, the short file identifier is 01, the preferred language is Chinese B. Select the PSE Association file by loopi

(+, ' OPERATIONS ', ' BOSTON '), insert into EMP values (7369, ' S MITH ', ' Clerk ', 7902,to_date (' 17-12-1980 ', ' dd-mm-yyyy '), 800,null,20); INSERT into EMP VALUES (7499, ' ALLEN ', ' salesman ' , 7698, To_date (' 20-2-1981 ', ' dd-mm-yyyy '), 1600,300,30); INSERT into EMP VALUES (7521, ' WARD ', ' salesman ', 7698,to_date (' 22-2-1981 ', ' dd-mm-yyyy '), 1250,500,30); INSERT into EMP VALUES (7566, ' JONES ', ' MANAGER ', 7839,to_date (' 2-4-1981 ', ' Dd-mm-yyyy '), 2975,null,20); INSERT

, ' BLAKE ', ' MANAGER ', 7839, ' 1981-05-01 ', 2850,null,30);INSERT into EMP VALUES (7782, ' CLARK ', ' MANAGER ', 7839, ' 1981-06-09 ', 2450,null,10);INSERT into EMP VALUES (7788, ' SCOTT ', ' ANALYST ', 7566, ' 1987-04-19 ', 3000,null,20);INSERT into EMP VALUES (7839, ' KING ', ' president ', NULL, ' 1981-11-17 ', 5000,null,10);INSERT into EMP VALUES (7844, ' TURNER ', ' salesman ', 7698, ' 1981-09-08 ', 1500,0,30);INSERT into EMP VALUES (7876, ' A

SELECT * from EMP; EMPNO Ename JOB MGR HireDate SAL COMM DEPTNO 1 7369 SMITH Clerk 7902 1 July-December-80 800 20 2 7499 ALLEN Salesman 7698 20月-February-81 1600 300 30 3 7521 WARD Salesman 7698 2 February-February-81 1250 500 30 4 7566 JONES MANAGER 783

Oracle's self-JOIN operationFor Oracle databases, there are two sets of grammars currently supported, one for Oracle's own SQL syntax and one for the standard SQL99 syntax, and two sets of syntax for Oracle's connection operations can be implemented separately. Of course, in terms of efficiency, there is no difference between the two. But from my point of view, Oracle's syntax is more concise.For example, we have a list of EMP, the table data is as follows[Email protected]> Conn Scott/tigerConne

-81 2850 7782 CLA RK MANAGER 7839 09-jun-81 2450 Ten 7788 SCOTT ANALYST 7566 19-apr-87 7839 KING President 17-nov-81 7844 TURNER salesman 7698 08-sep-81 0 7876 ADAMS Clerk 7788 23-may-87 1100 20 EMPNO ename JOB MGR hiredate SAL COMM DEPTNO DEP---------------------------------- --------------------------------------------------------------------------7902 AMY ANALYST 7566 03-dec-81 rows selected. Sql> The second step is

,to_date (' 1-5-1981 ', ' dd-mm-yyyy '), 2850,null,30); INSERT into EMP VALUES (7782, ' CLARK ', ' MANAGER ', 7839,to_date (' 9-6-1981 ', ' dd-mm-yyyy '), 2450,null,10); INSERT into EMP VALUES (7788, ' SCOTT ', ' ANALYST ', 7566,to_date (' 19-04-1987 ', ' dd-mm-yyyy ') -85,3000,null,20); INSERT into EMP VALUES (7839, ' KING ', ' president ', null,to_date (' 17-11-1981 ', ' dd-mm-yyyy '), 5000,null,10); INSERT into EMP VALUES (7844, ' TURNER ', ' sales

2850 - 7782CLARK MANAGER7839 the-June-Bayi 2450 Ten 7788SCOTT ANALYST7566 +-APR- the the - 7839KING President --NOV-Bayi the Ten 7844TURNER salesman7698 ,-SEP-Bayi the 0 - 7876ADAMS Clerk7788 at-May- the 1100 -

Yesimp_full_database CREATE DATABASE LINK nosys creat E Public DATABASE LINK NODBA CREATE public DATABASE LINK yesgrantee PRIVILEGE ADM-------------------------------------------------------------------------DBA CREATE databa SE LINK YES12 rows selected. Sql> Grant CREATE DATABASE link to Scott; Grant succeeded.Sql> CREATE DATABASE link Comparison_link Connect to Scott identified by Root using ' orac1 ';D atabase link created. Sql> show Useruser is ' SCOTT ' sql> s

(' 02-04-1981 ', ' dd-mm-yyyy '), 2975, NULL, 20);Insert into EMP (empno, ename, Job, Mgr, HireDate, Sal, Comm, Deptno)VALUES (7654, ' maritn ', ' salesman ', 7698, to_date (' 28-09-1981 ', ' dd-mm-yyyy '), 1250, 1400, 30);Insert into EMP (empno, ename, Job, Mgr, HireDate, Sal, Comm, Deptno)VALUES (7698, ' Blake ', ' manager ', 7839, to_date (' 01-01-1981 ', ' dd-mm-yyyy '), 2850, NULL, 30);Insert into EMP (empno, ename, Job, Mgr, HireDate, Sal, Comm

into "DEPT" VALUES (+, ' OPERATIONS ', ' BOSTON ');CREATE TABLE EMP(EMPNO Int (4) is not NULL,ename varchar (10),JOB varchar (9),MGR Int (4),HireDate Date,SAL Int (7),COMM Int (7),DEPTNO Int (2));INSERT into "EMP" VALUES (7369, ' SMITH ', ' clerk ', 7902, ' 17-12-1980 ', 800,null,20);INSERT into "EMP" VALUES (7499, ' ALLEN ', ' salesman ', 7698, ' 20-02-1981 ', 1600,300,30);INSERT into "EMP" VALUES (7521, ' WARD ', ' salesman ', 7698, ' 22-02-1981 ', 1250,500,30);INSERT into "EMP" VALUES (7566,

', ' SCOTT ', ' ALLEN ');=========================================================Iii. precedence of conditions in where1. Arithmetic operation2. Comparison operation3. Logical operation: Not>and>or① find a job as an administrator or an analyst, and a person with a salary greater than 2500Sql>select * from EMP where (job= ' MANAGER ' or job= ' ANALYST ') and Sal >2500;EMPNO ename JOB MGR hiredate SAL COMM DEPTNO---------- ---------- ------------- ---------- ------------ ---------- ---------- -