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Here is a brief summary of Python Oracle database operation related knowledge. Just sort out the previous experiments and notes. The test server here is CentOS Linux release 7.5. A machine for personal experimentation, testing and data acquisition. 1: Install cx_Oracle Here's a brief introduction to cx_Oracle. The following paragraph is exc ...

I. jdk installation Install jdk1.7.0_80 Unzip to / usr/local/jdk1.7.0_80 Modify environment variable vi/etc/profile II. Creating Users Create a group: group add Weblogic Create users: useradd-g Weblogic Weblogic Modify password: passwd weblogic Enter password*** III. Installation of Weblogic 12C ...

1. Backup databaseBoth RMAN and expdp can be used.2. Backup Software Directory (node1/2) tar -czvf /u01/grid.tar.gz /u01/app/11.2.0/grid --exclude=/u01/app/11.2.0/grid/rdbms/audit/* tar -czvf /u01/database.tar.gz /u01/app/oracle/ --exclude=/u01/app/oracle/admin/orcl/adump/* 3. Backup OCR (node1/2) [grid@vastdata01 ~]$ cd $ORACLE_HOME/bin [g ...

For these two kinds of locks, the performance of synchronized before JDK1.6 is far inferior to that of Lock, because synchronized needs to call the functions of the operating system and operate the kernel to complete, which is time-consuming. After JDK1.6, Oracle has optimized synchronized a lot, and sy ...

The official version of MySQL 8.0 has been released. MySQL 8.0 has added many new functions, which can be referred to specifically. MySQL 8.0 official version 8.0.11 release! "Article. MySQL 8.0 adds role management to user management, and the default password encryption mode has been adjusted from SHA1 to SHA2. At the same time, MySQL 5.7 ...

I. Preparations 1. Preparing the CentOS 7 System Environment Because it was installed in silent mode, without using a graphical interface, I chose the smallest installed server version of entOS 7. After installation, only the command line interface is available. 2. Download Oracle 11g (1) Oracle's official website: http://www.oracle.com/t ...

Isolation level Define how much a transaction is affected by other concurrent transactions. Problems caused by transaction concurrency Dirty Reading: One transaction reads data modified by another transaction that has not yet been submitted ...

Oracle Advanced Learning Paging 1,rowid rowid, which is generated and unchanged when creating records, is the unique identifier of physical location, pointing directly to the storage location on the hardware. ID is the only logical identifie ...

https://my.oschina.net/xinsui1314x/blog/1933045 Environmental Science Operating System: CentOS Linux release 7.4.1708 (Core) Oracle Version: 12cR1 Oracle's yum: http://public-yum.oracle.com/public-yum-ol7.repo Configuration of oracle install ...

1. Transaction isolation level 1.1 transaction-induced concurrency problems When multiple transactions run concurrently, if multiple transactions operate on the same data in the database at the same time, it is easy to cause concurrency problems. ...