Oracle

 Link: transparent http://www.eygle.com/archives/2011/09/transparent_data_encryption_performance.html encryption of Data columns inevitably results in performance impact; Oracle Database 11gR2, Oracle claims tablespace-level encryption, encryption

1. Score by ROWID  Select * from t_xiaoxi where rowid in (select rid from (select rownum rn, rid from (select rowid rid, cid fromT_xiaoxi order by cid desc) where rownum 9980) order by cid desc; Select * from t_xiaoxi where rowid in (select rid

Steps:1. Export data files from mysql Select sender, imsi, random_code, date_format (token_create_time, '% Y % m % d % H % I % s'), date_format (last_login_time, '% Y % m % d % H % I % s'), 1 as statusFrom tb_sms_token where last_login_time is not

The date format stored in the database is different from the date format in SQL.SQL> insert into test_date values (to_date ('2017-12-17 16:42:42 ', 'syyyy-mm-dd hh24: mi: ss '));  One row has been created. SQL> select to_char (date_col, 'syyyy-mm-dd

To uninstall an oracle database, follow these steps:1. Choose "start"> "Settings"> "Control Panel"> "Administrative Tools"> "services" to stop all Oracle services.2. Start-> Program-> Oracle Installation Products-> Universal Installer uninstalls all

@ Echo offSet sysUsr = systemSets sysPwd = 123Set usrname = test_ztSet pasword = test_ztSet sid = sid1 Set/p usrname = enter the user name [Press enter as the default value % usrname % ]:Set/p pasword = enter the password [Press enter to the default

[INS-35172] Target database memory (XXMB) exceeds the systems available shared memory ({0} MB) Solution When installing the Oracle 11gR2 database, an error is reported during installation:     [INS-35172] Target database memory (778 MB) exceeds the

Oracle integer functions include the following:1. Round (large) select ceil (-1.001) value from dual to large carryCEIL (-1, 0.12)-----------02. Round (small) select floor (-1.001) value from dual to small carryFLOOR (-1, 0.12)-------------1 3.

The method for starting Scott user in Oracle. In Oracle10g, (g stands for 'network') the Scott user in the database is locked during installation. When installing Oracle, you can directly unlock the user. If you forget to unlock the user, you can

In Linux, how does one start multiple Oracle instances? I believe that many beginners of Oracle will encounter this type of problem. I will give a brief introduction below. 1. Switch Oracle users: # Su oracle 2. Switch to the Oracle directory: #

1. Error description:Each generated sqlloder file is in good condition and has the same permissions, but an error is reported when importing the oracle database. The error is:SQL * Loader-704: Internal error: ulconnect: OCIServerAttach [0]ORA-12154:

Three implementations of isnumeric in OracleIf you have used asp, you should be familiar with the isnumeric function. This is a common function used to determine whether an input parameter is a number. There is no ready-made function in oracle to

Decompress instantclient.rar to the specified directory, for example, C: \ instantclient. In the root directory, create the NETWORK \ ADMIN directory and set the environment variable TNS_ADMIN = C: \ instantclient \ NETWORK \ ADMINPath = C: \

Problem description: 1. the remote connection is normal. You can use pl/SQL developer to link to a remote database, but the local database service cannot be linked after it is enabled. if the local Database Listener cannot be opened, enter lsnrctl

If you encounter a large amount of AWR data in your daily work, you can clear it as follows: SQL> select distinct dbid, db_name, instance_name from wrm $ _ database_instance; DBID DB_NAME INSTANCE_NAME ---------- --------- ---------------- 2691876695

1. Explain the differences between cold backup and hot backup and their respective advantages: Hot Backup is used to back up a database in archive mode when the database is still working. Cold backup refers to the backup after the database is closed,

Today, when I used Oracle paging to query data, I encountered repeated data. Some data could not be found. I was very depressed and thought about it. I found the problematic paging statement: SQL code select * from (select row _. *, rownum _ from

Solve ORA-00257: archiver error. Connect internal only, until freed this issue is due to archiving logs full. Solution: SQL> select * from V $ FLASH_RECOVERY_AREA_USAGE; FILE_TYPE commandid NUMBER_OF_FILES ------------ commandid ---------------

Sqlplus special command 1. disc [onnect]: log out of the database, but not sqlplus; 2. exit or quit, exit sqlplus; 3.c[ hange]/old string/New String, replace the old string of the current row with the new string 4.cl[ ear] To clear cl buff [er] to

(Create table Name (field) storage (buffer_pool keep); -- cache the table to the KEEP when creating the table. alter table name storage (buffer_pool keep ); -- cache the existing table to the create table name (field...) in the KEEP ..) storage