Database Administrator

-- Requirement Description: In signBook2, there is a column of date_time with a value of 201210201221. I need to change the first 2012 to 2014, so I wrote the following stored procedure-- _ Id is a column in the table and is the primary key

It is normal for programs to encounter exceptions during execution, and exceptions during programming are inevitable. However, an exception handling server is required. To ensure the normal execution of the program. An error occurs during the

Today, my colleague said that he has applied for a dump file exported from production and needs to import the test database for testing. The operations previously performed are basically export from the current database and import from this database,

PL/SQL subprograms include functions and procedures. The function here refers to the user-defined function, which is different from the system function. A subroutine is a PL/SQL block that completes a specific function. It is universal and can be

Backtround: I'm trying to set up processing ing between two SQL 2008 R2 databases on different servers in my internal network, as a test run before doing the same thing with two live servers in different locations.When I actually try and switch the

When writing SQL statements, we found that there are usually many implementation methods for the desired results. In the face of these implementation methods, how should we choose to be relatively optimal? This introduces the topic of this blog, how

Control File -Small binary files -Define the current status of the physical database -The loss control file must be fixed. -Maintain database integrity -Requirements: 1. The database is in the mount state when it is started 2. Database

We often encounter an SQL Performance problem in a session, but it cannot be determined which SQL causes a high DB performance problem. This is what we need to monitor this session through the dbms_monitor package. First, determine the session sid

Zookeeper Berkeley DB (BDB) is an efficient embedded database programming library. APIs are available in C, C ++, Java, Perl, Python, Tcl, and many other languages. Berkeley DB can store any type of Key/Value pairs (Key/Value Pair) and store

The and or operators are used to filter records based on more than one condition.And or operators And or can combine two OR more conditions in the WHERE substatement. If both the first AND second conditions are true, the AND operator displays a

1. Open SQL developer in the Start Menu; 2. Create a database connection Click the plus sign in the upper left corner. In the displayed dialog box, enter the user name and password. If the test succeeds, click Connect. Remember to write the role

The most confusing order of composite indexes is the order of index columns, which depends not only on queries using this index, but also on sorting and grouping. Some time ago I posted a post: where condition order and compound index field order.

The developer said that a package was created and some errors occurred during compilation. Prompt for PL/SQL: ORA-00942: table or view does not exists. This is an obvious error, that is, the error message is displayed either because the table does

SQL Server can quickly import data by using the following methods: CTE, OpenRowSet/OpenDataSource, BULK INSERT, bcp, and Shell.The following describes these methods in sequence.1. CTE first, let's look at what CTE is. Common Table expressions are a

Package project02_Order_management.util; import java. io. IOException; import java. lang. reflect. field; import java. lang. reflect. invocationTargetException; import java. lang. reflect. method; import java. SQL. connection; import java. SQL.

This self-study note is from the video Hadoop series on Yutube. url: Https://www.youtube.com/watch? V =-TaAVaAwZTs (one of them) I will not repeat it later Self-taught notes are prone to various errors. Please be careful. Hadoop is still used in

1. Add 6 hard disks (100 GB each. This can be done either through hot or cold addition, or by adding hard disks, using san storage to draw Luns, or adding multiple paths.At the operating system layer, the following sdb can identify such a lun. The

1. If you have a plsql client, you can use this user to log on and right-click all tables and Drop them. 2. If you have the permission to delete a user, you can: Drop user user_name cascade; With cascade, you can delete all associated user

The Function Room of the Database Control Language controls the user's access permissions to the database. The DBA determines the operation permissions of a user on a certain type of data. Oracle GRANT permissions using the GRANT statement and

In general, in the future, we will prevent users from deleting or clearing tables and data. You can directly grant them a small amount of permissions.For example, to prevent users from performing truncate operations, you can grant the following