oracle普通知识

1.连接配置路径一般在 oracle\product\11.2.0\= dbhome_1\network\admin下的tnsnames.ora文件：

此处需要非常注意空格，曾经因为空格问题连接失败,可复制粘贴服务端的配置

例子：

nocqb_155 =

(DESCRIPTION =

(ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.41.155)(PORT = 1521))

(CONNECT_DATA =

(SERVER = DEDICATED)

(SERVICE_NAME = nocqb)

)

)

2.远程连接失败如果监听有异常，修改服务端与tPrnsnames.ora同级的listener文件：

如：

SID_LIST_LISTENER =

(SID_LIST =

(SID_DESC =

(SID_NAME = CLRExtProc)

(ORACLE_HOME = C:\app\Administrator\product\11.2.0\dbhome_1)

(PROGRAM = extproc)

(ENVS = "EXTPROC_DLLS=ONLY:C:\app\Administrator\product\11.2.0\dbhome_1\bin\oraclr11.dll")

)

(SID_DESC =

(GLOBAL_DBNAME = nocqb)

(ORACLE_HOME = C:\app\Administrator\product\11.2.0\dbhome_1)

(SID_NAME = nocqb)

)

(SID_DESC =

(GLOBAL_DBNAME = noccase)

(ORACLE_HOME = C:\app\Administrator\product\11.2.0\dbhome_1)

(SID_NAME = noccase)

)

)

LISTENER =

(DESCRIPTION_LIST =

(DESCRIPTION =

(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521)

(ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.41.155)(PORT = 1521)

)

)

ADR_BASE_LISTENER = C:\app\Administrator

1.创建表：

create table myBook(

bookid number(10) not null,

bookname varchar2(40),

author varchar2(40),

bookprice number(4,2),

contraint book1_pk primary key(bookid));

2.自连接主要用来显示上下级或者层次关系的

3.oracle的字段名默认大写，如果表中的字段小写，那么在用到这个字段的时候必须加上""

4.oracle安装数据库实例时85%进度出现监听问题，可以关掉防火墙，杀毒软件，lsnrctl stop然lsnrctl start,

若还没解决，在环境变量中加入ORACLE_HOSTNAME = localhost，重启机器即可解决

5.查找日期类型：select * from TRACK_FLIGHT_LOG where csrq = to_date('2015-12-02','yyyy-mm-dd');

6.plsql不登陆进入：sqlplus /nolog