Oracle

Oracle data import and export imp/exp is equivalent to Oracle data restore and backup. The EXP command can export data from a remote database server to a local DMP file, and the IMP command can import the DMP file from a local to a distant database

Oracle divides a column into multiple columnsIn Oracle, we can use Listagg (Oracle 11g and above) to merge one column of multiple rows into one column, and now our requirement is to split one column into multiple columns.First create a table and

Oracle recursive query Create a table to build a table statement:CREATETABLESc_district (IDNumber (10)NotNull, parent_idNumber (10), NAMEVARCHAR2 (255 BYTE)Notnull); alter table sc_district addconstraint SC_DISTRICT_PK primary key

Original PowerDesigner to reverse engineer OracleObjectivePowerDesigner 15 Reverse engineering of the OracleClient 11gEnvironmentWIN7 64-bit systemOracle 11gOracleClient 11g ODACPowerDesigner 15Steps1,fileàreverse Engineeràdatabase2,dbms, select

Open and close under Oracle Linux1, start Oracle monitoring first to login user Oracle:su-oracleoracle@localhostbin]$ Lsnrctl--Start the Oracle Listener commandLsnrctl forLinux:version10.2.0.1.0 -Production on in-OCT- . +: $: GenevaCopyright (c)199

Installing the Database1. Set up user groups and users groupadd Oinstallgroupadd dbagroupadd operuseradd-G Oinstall-G dba oraclepasswd Oracle2. Create the installation directory and permissions mkdir-p/opt/Ora10gchown-R oracle.oinstall/opt/ora10g3.

Summarizes the frequent use of SQL for viewing Oracle databases and helps to optimize a robust system program for analysis.1. Current number of database connections:Select COUNT (*) from v$process2. Maximum number of connections accepted by the

1. Start the Oracle database:To switch to an Oracle User:[Email protected] ~]# su-oracleEntering the Sqlplus environment, the Nolog parameter indicates no login:[Email protected] ~]$ Sqlplus/nologLog in in Administrator mode:[Email protected] ~]$

Sqlplus Login Oracle Server query table display Chinese is garbledSql> select * from test11;Id----------NAME--------------------------------------------------------------------------------111??222??333??????Sql> Select Userenv (' language ') from

Dbms_random is a package that can generate random numbers or strings.Dbms_random.value method1, decimals (0~1)Select Dbms_random.value from dual;2. Decimals within the specified range (0~1000)Select Dbms_random.value (0,1000) from dual;3. Integers

--Resolve an issue where Oracle 11g cannot export empty tables--Execute the following statement to query the empty table in the database while generating the allocated space. Copy and execute the generated results.Select ' ALTER TABLE ' | |

Orabbix monitors oracle databases and orabbix monitors oracle databasesOrabbix monitoring oracle database 1 download :Http://www.smartmarmot.com/product/orabbix/download/2. Grant file executable permissions #chmod +x /opt/orabbix -R#chmod +x

Rownum, row_number (), and rownumrow_number in oracle Row_number () over (partition by col1 order by col2) indicates grouping by col1 and sorting by col2 within the group, the value calculated by this function indicates the sequential numbers after

Oracle generation random date and time 1. Generate a random date   For example, to generate an arbitrary date within January 1, 2015: /** Analysis: any date within, that is, the date range is (2015)* Can be converted to + (0,365 ),* In this example,

In one of the RAC decomposition steps, install the oracle 10.2.0.1.0 operation log on oracle linux 4u4, 4u410. 2.0.1.0 Exercise the oracle rac formation process. Step 1: First practice installing oracle 10.2.0.1.0 on 4u4. It is difficult to directly

Content of the eight Oracle12.1.0.2 files Oracle Database (des Oracle Database, Oracle RAC, and Deinstall)Note: you must download both zip files to install Oracle Database. P17694377_121020 _Platform_1of8.zipP17694377_121020 _Platform2017

Oracle12c installation, connection, and usage 1. oracle12c Installation See the following link: Http://www.bkjia.com/database/201503/380453.html 2. A ORA-12514 error occurred while connecting to the database. For more information about the solution,

Precautions for modifying the operating system on the Oracle Database Server Precautions for modifying the operating system on the Oracle database server: For standalone or ha1. There is no impact on the database itself. Because scn does not

Oracle Random Number Generation Method Dbms_random is a package that can generate random values or strings.   Dbms_random.value Method   1. Decimal (0 ~ 1)   Select dbms_random.value from dual; 2. decimal places in the specified range (0 ~ 10

How to use the analysis function to find the employees with the highest salaries in each department in the EMP table? The function is emp. The EMP table is an employee table in SCOTT, an Oracle test account. First, let's take a look at the data in