Oracle

What should I do if I use ORACLE to perform data sampling for data analysis and encounter a large amount of recorded data? Comprehensive analysis is unrealistic and unnecessary. The following describes the sampling methods and several common

Linux boot automatically starts ORACLE settings 1. After the Oracle database is installed: After dbstart and dbshut are executed, the system will prompt: [oracle @ oracle11g ~] $ Dbstart ORACLE_HOME_LISTNER is not SET, unable to auto-start Oracle

Install sqlplus and shell in Linux to query the database and download the rpm file, install orcacle sqlplus Java code rpm-ivh oracle-instantclient-basic-10.2.0.4-1.i386.rpm rpm-ivh oracle-instantclient-sqlplus-10.2.0.4-1.i386.rpm after installation

Oracle will inevitably have no space to recycle when it is used to shrink the tablespace database. If the space is too large, use the following method to recycle it. Query the space occupied by a table: [SQL] SELECT tablespace_name, 100 *

Two oracle transpose Methods: Method 1: SYS_CONNECT_BY_PATH, ROW_NUMBER () OVER (partition .. order ..), start with, connect by prior Combination Method 2: wmsys. wm_concat example: In table 1, one col1 corresponds to multiple col2 fields. In the

Listener error handling 1: Host Name and IP misplacement error message: [plain] [oracle @ odd ~] $ Lsnrctl status LSNRCTL for Linux: Version 10.2.0.1.0-Production on 01-MAY-2013 15:40:54 Copyright (c) 1991,200 5, Oracle. all rights reserved.

PL/SQL batch processing statements: bulk collect and FORALL contribute to optimization. We know that there are overhead for running SQL statements in PL/SQL programs, because SQL statements are to be submitted to the SQL engine for processing, the

Concepts of oracle locks-1. Locks 1. The concept of locks: a database is a shared resource used by multiple users. When multiple users concurrently access data, multiple transactions can simultaneously access the same data in the database. If such

Two temporary tables in the Oracle database. If we do not specify the data table when creating the data table, the table we create is a permanent relational table, that is, the corresponding data in this table will always exist unless it is deleted.

To convert a vertical ORACLE table to a horizontal table, assume that the following vertical table exists. The first column is id (which may be the id of a business data), the second column is type, and the third column is the value corresponding to

Oracle Hints statement usage 1. /* + ALL_ROWS */indicates to select the overhead-Based Optimization Method for the statement block and obtain the optimal throughput to minimize resource consumption. example: SELECT/* + ALL + _ ROWS */EMP_NO, EMP_NAM,

Oracle replication table structure, data 1. copy the table structure and data: create table table_name_new as select * from table_name_old 2. copy only the table structure: create table table_name_new as select * from table_name_old where 1 = 2; or:

Oracle export table structure and data exp/imp tool: with parameters: rows = y -- with data export import; rows = n -- without data export import, only transplantation structure. For example, export the structure of only three tables: exp

Oracle uses DBLINK to access GreenPlum for POC for integration and migration between multiple databases, and tries to use Oracle Gateway and Heterogeneous Service for transit access. It has been tested many times, it is found that the configuration

GL_SETS_OF_BOOKS the book table SET_OF_BOOKS_ID the book id name the book NAME CHART_OF_ACCOUNTS_ID the book Account System ID -- the relationship between the Organization OU and the book SOB. A ledger can be set to multiple units. A single unit can

The oracle job sample declare x number; begin sys. DBMS_JOB.SUBMIT (job => X, what => 'etlrund _ Date; ', nextdate => todate ('2017-08-26 01:00:00', 'yyyy-mm-dd hh24: mi: ss'), interval => 'trunc (sysdate) + 1 + 100', no_parse => FALSE); SYS.

[Oracle rich Shuai view series] I know v $ segment_statistics and send SR on MOS. Q: How is segment_statistics updated? Oracle's answer: v $ segment_statisitcs has been used for internal research since 9IR2 was introduced. [Answer: Sorry, I am

In plsql programming, the variable Declaration creates the first program hello worldbegin dbms_output.put_line ('Hello World'); end;/set serveroutput on; (the command that outputs the statement to the dos window) begin dbms_output.put_line ('Hello

For example, select * from tb_cod_field_desc where table_code_flag = '000000' start with superior_code = 10000110 connect by prior code = superior_code: start... connect... the following is an explanation: start with... in racle... connect by prior

Rlwrap installation error You need the GNU readline... first of all, you must know what rlwrap is, but I will repeat it. in linux and unix, SQL plus cannot be used up, down, or rolled back, and garbled characters may occur. Rlwrap is used to solve