Oracle

After the ORACLE database is started. This statement enables you to see all the parameters used by the Oracle database using the SELECT * from V$parameter . For Oracle 's parameter files, it is divided into spfile binaries and pfile text files.

First, install the software package required by Oracle (depending on the Oracle official documentation)can use# yum-y Install binutils* compat-lib* gcc-* glibc-* ksh libgcc-* libstdc++-* libaio-* make-* sysstat*For installation.Ii. creating user

Database stopped:Shutdown normalNo new connectionWait for the current session to endWait for the current transaction to endForce checkpoints and close files (consistent close)Shutdown transactionalNo new connectionEnd Current sessionWait for

The main contents include:(1) Three kinds of cycles and their simplification(2) Use of cursors(3) Exception handling(4) Stored procedures(5) Storage function(6) Trigger(7) Other PL/SQL operationsDefine variables---------------Loop loop---------------

Note: When you write the stored procedure again, begin and end are written in the For loop, so that you can write exception, let the error data roll back, log the error logs, commitKeywords: Oracle stored procedures1. Basic structureCREATE OR

The amount of space (table capacity) of statistical tables/* Generally, the table occupies three parts: Table data, table index, table blob field data */--1 Statistics the space occupied by a single table with (BLOB field)SELECT table_name, SUM

Oracle base data Type (4 classes):Character Type: stringCHAR (max.), nchar (max 1000, Unicode supported)---> fixed length, fixed length even if not full it automatically occupies these positionsVARCHAR2 (Max 4000), NVARCHAR2 (Max 2000, Unicode

Database Common keywords:CREATE TABLE --- Create a tableCreate a table with table name (column name type of column, column name Type of column ... )CREATE TABLE Z_course (ID number, Cour_code VARCHAR2 (), Cour_name VARCHAR2 (), p_cour_code VARCHAR2

public class Test {private static final SimpleDateFormat FORMAT = new SimpleDateFormat ("Yyyy-mm-dd HH:mm:dd");public static void Main (string[] args) throws SQLException {Oracle.sql.TIMESTAMP temp = new Oracle.sql.TIMESTAMP ();SYSTEM.OUT.PRINTLN

Introduction to Oracle Trunc function usageCore TIP: Introduction to Oracle Trunc function usage1.TRUNC (for dates)The date value that the Trunc function truncates for the specified element.Its specific syntax format is as follows:TRUNC

Select File#,name from V$datafile;Select File#,name from V$tempfile;SELECT NAME from v$controlfile;--control fileSelect Group#,sequence#,status from v$log;--redo log fileShow parameter spfile;--database initialization fileSelect

See deterministic many times, have been very puzzled, today did an experiment.We cheat Oracle to say it is a deterministic function, which is called only once in SQL.Assume that deterministic is not used . The values you can see are different. after

----------------------------multitable Insert------------------------------------------------Insert All----------------------------------------------------SELECT * from EMP;CREATE TABLE Sal_history (Empid Number (4), HireDate date, SAL number (7,2));

SELECT * from EMP; EMPNO Ename JOB MGR HireDate SAL COMM DEPTNO 1 7369 SMITH Clerk 7902 1 July-December-80 800 20

Create or Replace procedure imp_person_medical (V_t_table_name varchar2,v_result out varchar2) as/**Parameter: V_t_table_name TEMP Data Sheet*/V_sql VARCHAR2 (2000);V_error_count number;Begin----End Imp_person_medical:There is no difference between

Recently in order to improve efficiency in the company's business to do mybatis batch update, but to the Oracle database did not succeed in several times, and later found that mybatis the last missing a semicolon, may be mybatis internal do an

TRUNC (Number,num_digits)Number requires a truncated rounding.The num_digits is used to specify the number of rounding precision. The default value for Num_digits is 0. If the num_digits is a positive number, the num_digits bit after the decimal

1. query Table Space LocationSELECT * from Dba_data_files;-d:\app\administrator\oradata\orcl\***.dbf2. View Temporary tablespace locationsSELECT * FROM V$tempfile-d:\app\administrator\oradata\orcl\***_tmp.dbf3. Create a temporary table spaceCreate

The key role of Oracle 10g database:1, reduce management costs;2, improve performance;Enhancements to Oracle 10g include:1, high availability enhancement, new flashback ability, support rollback update operation;2, to enhance the security, easy to

--View all users under the database:Select from Dba_users;--View the user roles for the current connected databaseSELECT * from User_role_privs;--Create UserCREATE User by test;--Assigning authorizationGrant to -- assign permissions to allow