Oracle

I. Set the environment variable [oracle @ orcl ~] $ Cat. bash_profile#. Bash_profile # Get the aliases and functionsIf [-f ~ /. Bashrc]; then.~ /. BashrcFi # User specific environment and startup programs ORACLE_SID = orclORACLE_BASE

1. Oracle tracking FileThere are three types of Oracle tracking files: One is the background alarm log file, which records the activity of background processes during database startup, shutdown, and running, such as creating tablespaces, creating

Insert multiple tables.Most insert operations are for a single table. However, oracle supports insert statements for multiple tables. In terms of data warehouse extraction, transfer and loading (ETL, Extract Transform and Load) routines, you will

The index is like a dictionary directory. With the dictionary directory, we can quickly find the entries we need. The same is true for databases. With the Oracle database index, related statements can quickly locate the record location without

We know that Oracle 10 Gb introduces the recyclebin concept. When we delete a table without specifying purge, the system only renames the table to the name starting with BIN $, modify related data in the data dictionary.In the Administrator's Guide,

TRANSLATE ('Char ', 'From _ string', 'to _ string ')       The return value of TRANSLATE replaces each character in from_string with the string after the corresponding character in to_string. TRANSLATE Is a superset of the functions provided by

  SQL * LOADER is a data loading tool for ORACLE. It is usually used to migrate operating system files to ORACLE databases.   SQL * LOADER is large data Repository selection method, because it provides the fastest way (DIRECT, PARALLEL ). Now, let's

  When oracle 11g exports a database using exp, empty tables cannot be exported. Therefore, you must use a Data Pump to import and export the oracle database.   1. expdp   SQL> create directory name (for example, dmpbx) as storage address (for

  POP3 is called Post Office Protocol version3, that is, Post Office Protocol version 3rd. It is used by the user agent to obtain the mail on the mail server. POP3 uses the C/S communication model, and the corresponding RFC file is RFC1939. This

The two highly lethal commands compiled today can instantly kill Oracle. Next I will give a simple comment and demonstrate its power.$ Ps-ef | grep $ ORACLE_SID | grep-v grep | awk '{print $2}' | xargs kill-9$ Ipcs-m | grep oracle | awk '{print $2}'

Select a. *, rank () over (order by cj desc) pmFrom ((Select 'A' name, 1 cjFrom dual) Union (Select 'B' name, 1 cjFrom dual) Union (Select 'C' name, 2 cjFrom dual) Union (Select 'D' name, 3 cjFrom dual) Union (Select 'E' name, 3 cjFrom dual) Union

The main function of minus operations is: When two tables or two query results are performed, returns records in the first table/query result that are different from the second table/query result. For example, the data in Table A is as follows: id

The difference between the Oracle database and the MySQL database is what we will introduce in this article, hoping to help you. 1. group function usage rules: Group functions in mysql can be used at will in select statements. However, if a group

I have read articles on the Internet, and there are several possible reasons for Garbled text: 1. operating System Character Set 2. character Set of oracle server 3. character Set of the Client 1. view the oracle Character Set Java code select

If you do not enable index monitor, you can determine whether the index has been used. If you want to know whether an index has been used, the traditional method is to enable index monitor. However, this method has two shortcomings: (1) it will

Oracle replaces a specific string keyword in clob: replace, dbms_lob.instr Step 1: Determine whether clob contains a specific string: for example, "/admin/ewebeditor/uploadfile/" Keyword: dbms_lob.20.code: [SQL] select st. id, st. content from

Oracle's X $ table series-X $ KSMSP has the following meanings: [K] ernal [S] torage [M] emory Management [S] GA Hea [P] each row represents a chunk in the shared pool. Let's take a look at the structure of x $ ksmsp.: SQL> desc x$ksmsp Name

ORACLE uses RMAN to manage archived logs. oracle usually uses rman to manage archived logs. Normally, the 1 expiration policy can be deleted as part of the Backup set. Crosscheck archivelog all; delete expired archivelog all;  2. Based on the

The inline view embedded view is called the inline view, which is also called the inline view. To put it bluntly, it is the view created during execution. For example, select... from (select... from (select ...)), the select statement used as the

A brief description of oracle expdp impdp using the Data Pump expdp. impdp can import and export data on the server side, which is highly efficient without setting the environment variable NLS_LANG, by default, the database will go to the character