Database Administrator

Oracle Study Notes: sqlplus User Logon 1 sqlplus Login Local login (log on to the database server) Oracle Logon Sqlplus account name/password as role name 1.1 sys Login Example: sqlplus sys/oracle ERROR: ORA-28009: connection as SYS shocould be as

Oracle cross-origin access to other instance data in dblink Mode When you want to access data in another database table across local databases, dblink of the remote database must be created in the local database, dblink allows you to access data in

Oracle functions for processing decimal digits ()1. Take the rounded decimal placesSelect round (1.2345, 3) from dual;Result: 1.2352. retain the two decimal places.Select trunc (1.2345, 2) from dual;Result: 1.23 Select trunc (1.2399, 2) from

Recently, I encountered several problems when I copied the Oracle Home ($ ORACLE_HOME) directory to install Oracle. First, the Oracle OS users, groups, kernel parameters, and environment variables (~ /. Bash_profile). For those who have installed

Install There are two ODBC types in linux: unixODBC and iodbc. Because wxGTK supports iodbc, you must install iodbc before installing wxGTK. When freetds is installed later, unixODBC may also be installed based on the environment and dependency. The

Three default system users Username and password Sys change_on_install (highest Network Administrator) Manager system local administrator Scott tiger common user 1. Start the cmd command of the Oracle listener: 1: name of the lsnrctl start listener (

I want to use MySQL in linux for my work needs today. After VM 7.1.3 is installed, the Red Hat Linux 2.6.18 is installed as needed ([Red Hat Enterprise. linux.5]. TLF-SOFT-RedHat.Enterprise.Linux.5.Update.2-XiSO.iso under the donkey), and from the

There are three main methods for MySQL Data Synchronization: 1. Use the MySQL database synchronization function2. Use the features of the MySQL database (the database has a fixed directory and is stored as a file) To synchronize the database

I. Start with the question During the development process, if the Oracle DDL statement and DML statement need to be processed in one transaction, the method either succeeds or fails. SQL server and other databases can solve this problem because it

MySql performs the JDBC join (Add/delete/modify/query) operation, and mysqljdbc Video address: http://www.tudou.com/programs/view/4GIENz1qdp0/ Create BaseDao Package cn. wingfly. dao; import java. SQL. connection; import java. SQL. driverManager;

[Translated from mos] Using index quick full scan (index ffs) to avoid full table scan, mosffs Using index quick full scan (index ffs) to avoid full table Scan Reference Original:Index Fast Full Scan Usage To Avoid Full Table Scans (Doc ID

[Translated from mos] SYS_OP_ C2C full table scan (fts)/full index scan, sys_op_c2cfts SYS_OP_ C2C full table scan (fts)/full index Scan Reference Original:SYS_OP_ C2C Causing Full Table/Index Scans (Doc ID 732666.1) Applicable:Oracle

In-depth analysis of MySQL ERROR 1045 (28000) and mysql28000 After a user is created in MySQL over the past few days, the access request is denied. The ERROR code is ERROR 1045 (28000 ). I searched the internet for a long time and found many

Use DBCA (database configuration assistant) in linux to create an oracle database and dbcaoracle Prerequisites: switch to the graphic interface Go to the bin directory of Oracle and run dbca as the oracle user. The effect is the same as that of

Solution: QSqlDatabase: an instance of QCoreApplication is required for loading driver plugins, qcoreapplication When QSqlDatabase is used, the error QSqlDatabase: an instance of QCoreApplication is required for loading driver plugins is reported

1. float TypeThe float column type cannot be found by default. The precision must be specified,For example, numFloat,InsertTable (num) values (0.12); select* From table where num = 0.12, empty set.Num float (9, 7 ),InsertTable (num) values (0.12);

I tried to build a simple LAMP environment, but I found that there are so many problems. (By default7 # zbphp.com) In many cases, the prompt for installing Mysql is via yum one-click installation. The shell command is as follows: yum install

At work, I will inevitably encounter mysql compiled and installed by my predecessors. I suddenly found that mysql does not support the innodb Storage engine. Let's take a look. 1. Check whether mysql supports the innodb Storage engine. Mysql> show

When I was writing a stored procedure, I used the start time and end time to create a view. So I wrote a process like this: Procedure prc_CreateViewOBookTcert (p_startdate in date, -- start date of statisticsP_enddate in date) -- end date of

From the definition, we can see that the Schema is a set of database objects. To distinguish each set, we need to name this set, these names are the nodes with similar user names that we see in the Enterprise Manager Solution. These nodes with