Oracle

--------- Mathematical functions 1. Absolute ValueS: select abs (-1) valueO: select abs (-1) value from dual2. INTEGER (large)S: select ceiling (-1.001) valueO: select ceil (-1.001) value from dual 3. Round (small)S: select floor (-1.001) valueO:

Some systems may have high requirements on the system's response to high data concurrency (for example, the flight ticket booking system). This article uses Oracle's lock table to solve this problem: The key code in Procedure is as follows: ---------

I used to know that Windows only has a recycle bin. Today I heard that Oracle also has a recycle bin! In Oracle, a table may be accidentally dropped. If regular backup is not performed, it will cause a lot of trouble. In some cases, daily data is

Authoritative Performance Testing Organization (TPC) was confirmed on December 3, the previous day Oracle submitted the names of the T3-4 Supercluster, with a total of 30 249 transactions per minute (transactions processed per minute. The original

The following are some statements about temporary tablespace learned:-- 1. view temporary tablespace (dba_temp_files view) (v _ $ tempfile view)Select tablespace_name, file_name, bytes/1024/1024 "file_size (M)", autoextensible from

Oracle over function usage rank () over ([query_partition_clause] order_by_clause) dense_rank () over ([query_partition_clause] order_by_clause) can be grouped by specified fields, sort the result set of the same grouping field. partition by is the

The usage of copy from in oracle Java code 1. syntax and usage instructions 1.1 syntax below let's look at the syntax and usage instructions of SQL * Copy Command. Before interpreting the syntax of SQL * Plus Copy Command, we must make it clear that

The SQL code create or replace package p_view_param is function set_param (num varchar2) return number; function get_param return varchar2; end p_view_param; create or replace package body p_view_param is paramValue varchar2 (4000); function

Linux script command record (database) operation steps for DBA, often encounter Database Upgrade or apply patch, and sometimes need to run a large number of scripts. For these operations, we want to output files simultaneously on the screen for

Libg2c. so.0 is needed by compat-gcc-34-g77-3.4.6-4.i386 handle errors Oracle requires compat-gcc upon installation, I encountered the following problem during RHEL5.4: [root @ localhost rpm] # rpm-ivh compat-gcc-34-g77-3.4.6-4.i386.rpmwarning:

How to handle the '&' symbol in Oracle SQL statements is automatically escaped if the '&' symbol appears in the SQL statement; the value of the string to be followed after the & symbol is required. For example, update tablename set columnName =

Oracle 10g rac standby automatic log deletion script [plain] #! /Bin/bash export ORACLE_HOME =/opt/oracle/product/10.2.0/db_1 export ORACLE_SID = standby1 export ARCHIVE_DIR =/log/archivelog export LOG_FILE =/home/oracle/logs/del_archive.log if [! $1

The partition table partition granularity is too large to solve the oracle database. performance problems occur in the afternoon. 1. Check the cpu, memory, io, and other performance parameters of the two servers and find that the CPU usage is close

Oracle SQL statement concatenation character Java code select city_std | '/' | stationname as name_std, city_std from station s, (select substr (s. name_std, 0, instr (s. name_std, '/')-1) from dual) | '. '| (select substr (getxtxx (s. maintainunit),

Oracle user-maneged recovery (1) I. disable database recovery in non-archive mode. shutdown immediate; shut down the database 2. use the operating system command to copy the latest backup (data files and control files, if log files are backed up) 3.

DML statement and table join Cartesian Product: (1992) SQL> select ename, dname from emp, dept; (1999) SQL> select ename, dname from emp cross join dept; query the same number in the middle of emp and dept: SQL> select ename, dname from emp, dept

The DBMS_HPROF package is used to collect PL/SQL Performance information. The DBMS_HPROF package is an oracle 11g tool, which is a combination of DBMS_PROFILER and DBMS_TRACE. here is a simple demonstration of how to use the DBMS_HPROF package to

Oracle basic code learning /* ------------ Orcale function ---------------- */1. character function LOWER () LOWER case UPPER () UPPER case INITCAP () connect the first letter to the CONCAT () string (you can also use "| ") functions are connected. /

[PL/SQL] How to implement complex grouping, subtotal, and aggregate -- Test code create table t_dist (TYPE_CD NUMBER, BUYER_ID VARCHAR2 (50), ORDER_DT DATE, SO_ID VARCHAR2 (50) not null, STOCK_ID VARCHAR2 (50) not null, UNIT_PRICE NUMBER, discount

[Oracle] After Oracle is set to restart automatically when the server is started in Linux, the database does not restart. Only then can I find that all databases have not been set to enable automatic restart, to prevent me from waking up from my