Database Administrator

The day before yesterday, the customer called and said that the background database of the GPS inspection system had crashed because the space allocated to the image storage disk was insufficient and he adjusted the partition. I asked him to back up

Installing a database in Linux causes a lot of trouble. The following is one of the troubles: After the innodb database engine is installed, find a lot of information, which is roughly as follows: 1. Remove # skip-before innodb # 2. Delete the

Oracle 10 Gb or later A long string is split into multiple rows. The regular expression is used to split a string: Select dbms_lob.substr (regexp_substr ('abc, 1234, ABCD, test', '[^,] +', 1, x. n) field from dual, (select rownum n from dual

After installing Oracle 11 GB in VMware 7.14, it was found that sqlplus could not be started. I searched the internet. It is estimated that the environment variable is not set. The current oracle is installed in/fantlam/oracle/app/oracle/product/11.2

1. xml file {Call GYL_COMMON.GETGROUPNUM (# {IN_PARAMETERID, jdbcType = VARCHAR, mode = IN },# {IN_STEELID, jdbcType = VARCHAR, mode = IN}, null,# {OUT_GN, jdbcType = INTEGER, mode = OUT },# {RST, jdbcType = CURSOR, mode = OUT, resultMap =

I just tested a program and reported an error saying that the data was not found: Rochelle date1! = L_date2L_date1 = 26-MAY-11, l_date2 = 26-MAY-11 ...... It turns out that it was nls_date_format. Oracle uses built-in programs such as

1. Description of the pseudo column on the official website From: 11gR2 Http://download.Oracle.com/docs/cd/E11882_01/server.112/e17118/pseudocolumns007.htm#SQLRF50953 Foreach row, ORA_ROWSCN returns the conservative upper bound system change number (

Test environment: Linux 5.4-32-bit, Oracle 11.2 Create a test table space: SQL> create tablespace tablespace1 2 datafile '/db/app/oracle/oradata/orcl/tablespace1.dbf' 3 size 10 m; Tablespace created. SQL>   Create a test user and specify it as the

It is important to back up your database when database tables are lost or damaged. In the event of a system crash, you must be able to restore as much data as possible from your table to the State at the time of the crash. This document describes

In Oracle databases, backup scripts can be executed on the command line, but cannot be executed on crontab. How to determine whether crontab is valid for oracle users in Linux. You can write a simple script that only contains the date command and

Guidance: Part 1: The following steps fully demonstrate the job creation process: Part 2: job-related knowledge: Part 3: Practical Application We found that the job owner must be used to delete jobs, and sys cannot delete other jobs! (First

Summary of several methods for disabling and starting Oracle:There are several startup methods:1. startup nomountNon-installation startup. In this mode, you can execute: re-build the control file and re-build the database. Read the init. ora file

The most efficient way to delete duplicate records is to use rowid as an example. Delete from emp e where e. ROWID> (select min (X. ROWID) from emp x where x. EMP_NO = E. EMP_NO ); 1. Search for redundant duplicate records in the Table. duplicate

When using Oracle, there is a big difference from the previously used SQL server. in Oracle, users are a key and delicious thing. Oracle ranks the second largest among large databases. The largest database is db2 and the third database is sybase.

Create or replace function fn_get_myjob_interval return date isResult date;V_nextdate date;V_nexthours number;BeginIf to_number (to_char (sysdate, 'dd')> = 25 thenBeginSelect max (t. activation_date)Into v_nextdateFrom emesp.

Grant the user a connect role and a resource role: Grant connect, resource to user; Permissions granted to the user after successful running: CONNECT role: -- is the most basic and typical right granted to end users. Alter session -- modify a

1. Introduction to Oracle dml SQL rollback LogicDatabase transactions consist of one or more DML (insert, update, delete) SQL statements. We know that the Oracle database uses the UNDO tablespace to store transaction rollback information during DML

-- Filter special sessions based on the machine name and SQL _HASH_VALUE and form a batch kill script SELECT 'alter system kill session ''' | c. sid | ''| ',' | c. serial # | ''';'FROM v $ session cWHERE c. MACHINE = 'hffwbz1 'and c. SQL _HASH_VALUE

[This article only records the upgrade process, does not discuss the advantages and disadvantages of the two versions, and the current database on this website is relatively simple, there is no stored procedure or anything, so the same method cannot

Because MySQL currently does not support dynamic parameter paging, you can either pass the SQL statement in the stored procedure or write a string connection method by yourself. Method 2 Write one line for each place to be split and clear BEGIN