Oracle

Create Table T1 (ID number (10), description varchar2 (50), constraint t1_pk primary key (ID )); Create sequence t1_seq; Insert into T1 values (t1_seq.nextval, 'one '); Insert into T1 values (t1_seq.nextval, 'two '); Insert into T1 values (t1

A process was recently tested: 1. Use tepro to create a vector layer and save it to the SHP format; 2. Use FME to import the SHP file to Oracle Spatial; 3. Release vector layers in Oracle Spatial into WFS-T services through SFS; 4. Load the

Today, we are doing an experiment with records/s inserted into the Oracle database. Both servers locally copy a million record table to another table with the same structure. One server took 12 s and the other one took nearly 2 minutes. Generate an

Sysdate indicates that the system date dual is a virtual table. 　　Date Functions[Focus on the first four date functions] 1. add_months [returns the date after the specified month plus (minus) (Before)] Select sysdate S1, add_months (sysdate, 10) S2,

1. merge two fields in the table into one display: SQL> select ID | stu_name as test from student; Test----------------------2007112810 Guo Xiaomei2007112812 Zhang Dayu2007112813aaa2007112814 Wang dazhi2007112815 Yi Jianlian2007112513 teacher You

In the data warehouse, null values are used to indicate conditions in which the actual values are unknown or ambiguous. In a table, if a column in a row does not have a value, it is called null ). For any data-type column, you only need to use the

I. Main Content There are many factors that affect the performance of ArcSDE, but in the final analysis, there are two aspects: the configuration of Oracle and ArcSDE in the background. Oracle not only includes database component size definition,

Today, I tried to use C ++ to operate Oracle databases. The steps are as follows: 1. Install occi If the Oracle database does not install occi by default, you can download the same version of the API from the official website, address:

When you use the SQL language to publish a query statement to the database, Oracle will generate an "Execution Plan", that is, the data search scheme through which the statement will be executed, whether to scan the entire table or search by index.

Function indexing concepts:Function-based index is a new product since 8i. It has the ability to index and calculate columns. It is easy to use and provides computed values, the query performance is improved logically without modifying the

In order to maintain its strongest and most flexible database position, Oracle has been creating new mechanisms in recent releases to simplify and block the storage of tables and indexes. Starting from Oracle8i, OracleTablespaceAutomate object

Recent studies have found that the indexes used by Oracle databases have never reached 1/4 of the number of available indexes, Or its usage is different from the intent of the initial design. Unused indexes waste space and reduce DML The speed,

Before executing an SQL statement, Oracle needs to analyze the statement execution plan and then execute it according to the execution plan. The execution plan of the Analysis Statement is completed by the optimizer. In different cases, an SQL

1. log on to 9.2.0.1 as sysdba and delete public synonym xmlconcat & function xmlconcat C:> sqlplus/nolog SQL> connect/As sysdba SQL> drop public synonym xmlconcat; SQL> drop function xmlconcat; 2. Shut down normally and stop all Oracle

[Original] common Oracle hint usage 1./* + all_rows */It indicates that the overhead-based optimization method is selected for the statement block, and the optimal throughput is obtained to minimize the resource consumption.For example:Select/* +

Original article: http://www.softhouse.com.cn/news/show/1469.html The Oracle database provides several different methods for starting and disabling databases. This article describes the differences between these methods and their respective

 I. session status description Oracle session has the following statuses: Active-sessioncurrently executing SQL Inactive Killed-sessionmarked to be killed Cached-sessiontemporarily cached for use by Oracle * XA Sniped-sessioninactive, waiting on the

1. alerts and metrics description Official link: Monitoring and tuning the database Http://docs.oracle.com/cd/E11882_01/server.112/e10897/montune.htm#CACCIHAB   Alerts help you monitor your database. most alerts between Y youof when particle metric

  It took more than half a month to study Oracle Golden Gate. Let's talk about a process of learning Gg first. All references are official documents. The links to the official website are as

[Ins-20802] Oracle Net configuration assistant failed. This error message is displayed when Oracle 11g R2 is installed. I have never encountered a similar problem during previous installation.. It turns out to be a problem with 64-bit and 32-bit