Oracle

Java.sql.SQLRecoverableException:IO error:connection ResetAt Oracle.jdbc.driver.T4CConnection.logoff (t4cconnection.java:612)At Oracle.jdbc.driver.PhysicalConnection.close (physicalconnection.java:5094)At Com.sms.send.StartTaskNew.run (smssend.java:3

As a novice, learn Oracle, and even install Oracle feel the struggle!After continuous search, study, try to find some more useful "guidance", listed as follows:1. http://www.2cto.com/database/201208/150620.html2. http://wenku.baidu.com/link?url=

SummaryStudents who often write SQL may use both the Union and UNION all keywords, and perhaps you know that using them can combine the result set of two queries.So what's the difference between them? Here's a simple analysis.ComparisonUnion: Set

Oracle should be familiar with how to view and set the maximum number of connections for an Oracle database. Let's go over it again. To view the current number of connections, you can use SELECT COUNT (*) from v$process;Maximum number of

1 Preface some global variables or constants are often encountered during the implementation of a program. This variable or constant is often stored in the global variables of the temporary table or foreground program during program development,

? Group functions: – Type and syntax – Use AVG, SUM, MIN, MAX, count– to use the DISTINCT keyword in group functions – Null values in group functions What is a group function The group function evaluates the rowset and provides a

The CBO shows that a full Oracle index scan is more efficient than a full-table scan, based on statistical values, and that the data queried at this point must be directly available from the index.When you are learning Oracle, you may encounter

Oracle more and more in the latest work, although they can also write some sql, stored procedures, triggers and so on, but the database management is still unfamiliar, and now will own the recent learning step by step. How to start Oracle on

Deformation of the nearest point pair, the key is to calculate the distance, if the same point, the direct decision to infinity can be.Other gossip:(1) For some reason, was forced to use the C + + for the time being.(2) long time no brush problem,

The V$sql_plan view provides a way to check the execution plan of a cursor that is still in the library cache. The information in this view is very similar to the information in the Plan_table view. However, EXPLAIN plan shows the theory that can be

At noon one day, some users reported system problems one after another, saying that the process was abnormal, the to-do list was not gone, and the to-do list could not be opened. The Maintenance Engineer began to analyze the problem. The clear

One table is named tb, the field segment is named name, and the data type is nchar (20 ).1. If the field data is empty, you can directly execute the following command regardless of the field type:Alter table tb modify (name nvarchar2 (20 ));2. If

1.1 symptom description UseExpAn error occurred while exporting data. The following error message is displayed: EXP-00008: ORACLE error 942 encountered ORA-00942: table or view does not exist EXP-00024: Export views not installed, please sort y

Some special problems in a cluster environment 1.1 Concurrency Control In a cluster environment, key data is usually shared and stored, for example, on a shared disk. Each node has the same access permission to the data. In this case, there must be

1. query the number of columns in the table Select count (column_name) from user_tab_columnswhere table_name = 'table name'; -- the table name is capitalized.Or: Select count (column_name) from user_tab_columns where table_name = upper ('table

Concept of high water level:All the oracle segments (segments here, for ease of understanding, we recommend that you use segment as a synonym for the table) have an upper limit to accommodate data within the segments, we call this upper limit "high

Oracle RAC upgrade test is performed in the test environment today. The original version is 11.2.0.3.0 and you want to upgrade it to 11.2.0.4.0, however, during the runinstaller process, [INS-06006] Passwordless SSH connectivity not set up between

Ora-00600 [KGHLKREM1]Symptom:Alert Log error:Sat May 18 07:59:47 2013Errors in file/oracle/PP/saptrace/usertrace/pp_ora_rj630.trc:ORA-00600: internal error code, arguments: [KGHLKREM1], [0x7000008C2000020], [], [], [], [], [], [], []Sat May 18 07:59:

[Overview] Those who have just been familiar with oracle may often be confused by the word rowid and rownum. Figuring out these two guys will be of great help for us to write SQL statements. I will introduce them as an example below, let's briefly

Oracle recommends that the OLTP (on-line TransactionProcessing) system accounts for 80% of the total system memory, and then allocates 80% to SGA and 20% to PGA. That isSGA = system_total_memory * 80% * 80%PGA = system_total_memory * 80% * 20%1.