Add auto-incrementing column in Oracle This is because the database of the other party is Oracle during project creation, and the identity () cannot be the same as that of MSSQL during auto-increment. Create sequence UserID_sequence -- create a
Introduction to PostgreSQL user roles and their attributes 1. Users created by create role do not carry the LOGIN attribute by default, while users created by create user have the LOGIN attribute by default, as shown below: Postgres= # Create role
Oracle learning-in-depth analysis of Buffer Cache Oracle learning-in-depth analysis of Buffer Cache Server process and database buffer cache: When the server needs a block, it needs to read the block in series steps: 1. First, the server uses the
ORA-01157 in Oracle Database: unable to identify/lock data files Environment: SLES 11 sp1 + RAC 220.127.116.11.7 I am about to take a vacation. I checked the database and found that node 2 of the billable billingdb database has the following error:Fri Apr
Expdp impdp Database Import and Export commands 1. Create a logical directory. This command does not create a real directory in the operating system. It is best to create a directory as an administrator such as system.Create directory dpdata1 as 'd:
Simple configuration of ASM Environment DescriptionSystem: Red Hat Enterprise Linux Server release 5.4 (Tikanga) Database Version: Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 add Disk Add three hard disks for the ASM disk group: It is
How to check the storage engine type of MySQL Data Tables on Linux Question: I want to know whether my MySQL database is of the MyISAM or Innodb type. How can I check the MySQL database table type? MySQl mainly uses two storage engines: MyISAM and
Oracle functions-advanced Below are some of the Oracle functions-advanced: 1. CATSTRExample: select catstr (COLUMN_NAME) NAME_LIST FROM DBA_TAB_COLUMNS where trim (TABLE_NAME) = 't_rz_dkdata '-- the query result is in a column.2. INSTR () string
How to locate and kill bad MySQL queries? Sometimes, the complexity of relational database systems will confuse you, but fortunately, using MySQL tools to manage queries can avoid these complexities. In this tutorial, I will show you how to find and
MySQL optimization summary on Linux Currently, most of the MySQL running environments are on Linux. Here we provide some general and simple policies on how to optimize MySQL on the Linux operating system. These methods help improve MySQL performance.
Use mysqlbinlog to restore data based on location or time point MySQL backup generally uses full backup and log backup. For example, a full backup is performed every day and a binary log backup is performed every hour. In this way, you can use full
Oracle merge into syntax 1. Usage of merge:Merge into is a new syntax added by Oracle 9i. It is supplemented at 10 Gbit/s to merge update and INSERT statements and perform join queries with another table based on one table or subquery, match the
Whether the Oracle database query object is locked and unlocked For details about whether the Oracle database object is locked, see the following SQL statement and the unlock process: -- Query the locked objects of the current userSelect B.
Query the size of a table with a lob field in the Oracle database Note: Because the lob field has an independent lob segment for storage, for a table with a lob field, you cannot only query dba_segments. The following scripts are from: How to
Statement used to query dead transactions in Oracle Statement used to query dead transactions in Oracle SQL> SELECT KTUXEUSN, KTUXESLT, KTUXESQN,/* Transaction ID */2 KTUXESTA Status, KTUXECFL Flags, KTUXESIZ3 FROM x $ ktuxe4 WHERE ktuxesta! =
Oracle Study Notes: Use of the graphic management tool EM Use of common Oracle learning notes tools-EM Graphics Management Tool em Server 1 Ensure Listening Starts -----> grid Lsnrctl status Or Netstat-tunlp | grep 1521 If not Lsnrctl start 2.
Modify the RAC address in Oracle 10 GB This test is based on Oracle 10.2.0.5 SQL * Plus: Release 10.2.0.5.0-Production on Tue Jul 29 20:45:16 2014 Copyright (c) 1982,201 0, Oracle. All Rights Reserved. Connected:Oracle Database 10g Enterprise
Analysis and Summary of several names that are easily obfuscated in Oracle We know that various names in Oracle often appear in our configuration files, which are roughly as follows: DB_NAME, INSTANCE_NAME, SERVICE_NAME in init. ora When configuring
Draw a sequence chart-use Gnuplot A time sequence chart is a common data plot. The most typical time sequence data is weather data. The weather temperature and humidity change with time, this article provides an example of using gnuplot to plot the
Generate DEM using big data in AcGIS When DEM is generated in ArcGIS, the data sources used are usually some height points and contour lines. These height points and contour lines are dense and may contain tens of millions or even hundreds of